Which statement most accurately distinguishes rightsizing from a commitment-based purchasing discount?
Hard · Choose one
Explanation
Answer: A. The two levers act on different factors of the same equation. Rightsizing reduces the quantity of resource-hours consumed by fitting the resource to the workload. A commitment reduces the price per resource-hour in exchange for a usage pledge. Applying rightsizing first is important, because a commitment made against an oversized baseline locks in the excess.
B. AWS provides recommendations but does not resize customer resources on its own, and commitments are purchased directly rather than through a support case.
C. Both apply broadly. Storage can be rightsized by class and volume size, and commitment models cover compute and several other service families.
D. This is inverted. Rightsizing is a configuration change with no term, whereas commitments carry a fixed one-year or three-year term.
32
A company's on-premises storage array is filled to 60 percent, but it was purchased at three times the capacity needed at the time in order to cover four years of projected growth. Which cloud economics concept most directly addresses this pattern?
Hard · Choose one
Explanation
Answer: D. Buying four years of growth up front is precisely the fixed expense the cloud model replaces. Cloud storage grows as data is written and is charged on what is stored, so the money for year four's capacity stays in the business until year four, and a forecast that turns out to be wrong costs nothing.
A. Spare capacity is not fault tolerance. Fault tolerance comes from redundant components and the ability to keep operating when one fails.
B. Some storage software is licensed by capacity, but licensing is not what makes buying three times the needed capacity wasteful. The waste is the timing of the purchase.
C. Volume discounts may reduce the unit price of the array, but a discount on capacity that sits empty for four years is still money spent early for no return.
33
An architect claims that moving a batch workload from Amazon EC2 instances to a serverless service improves cost efficiency. Which reasoning best supports the claim?
Hard · Choose one
Explanation
Answer: A. The saving comes from the shape of the demand. An intermittent workload leaves EC2 instances idle between runs, and idle instances are billed at the same rate as busy ones. With a serverless model the charge is tied to invocations and execution duration, so the gap between runs costs nothing. This is the consumption model applied to a workload whose utilization is naturally low.
B. Serverless services are billed on usage, not at a flat monthly rate. Predictability comes from understanding the workload, not from a fixed fee.
C. Execution speed depends on the code, the runtime, and the resources allocated. Serverless is not inherently faster, and cold starts can add latency.
D. Data transfer and storage are charged normally. Only the compute model changes.
34
Which statement correctly describes the relationship between automation and cost in a cloud environment?
Hard · Choose one
Explanation
Answer: A. Automation works on both sides of the bill. It reduces the operational effort spent on repetitive tasks, freeing people for higher-value work, and it applies cost-saving actions reliably: scaling in when demand falls, stopping non-production environments outside working hours, and expiring data on schedule. Manual equivalents are performed inconsistently or forgotten entirely.
B. Automation changes exactly what is consumed, because scaling and shutdown decisions determine how many resource-hours are billed.
C. Well-designed automation reduces consumption by removing idle capacity. Uncontrolled provisioning is a governance failure, not a property of automation.
D. The benefit is reallocation of effort rather than headcount reduction. Teams typically redirect that time toward architecture, security, and product work.
35
A company reports that after migrating, its AWS bill grew steadily while its workloads did not. Which explanation is most consistent with cloud economics practice?
Hard · Choose one
Explanation
Answer: A. The same self-service that makes the cloud fast also makes it easy to leave things running. Without attribution, ownership, and regular review, forgotten test environments, detached volumes, unused snapshots, and instances sized for a load test quietly accumulate. This is why cost optimization treats cloud financial management as an ongoing organizational capability, supported by analyzing and attributing expenditure to the teams that own it.
B. AWS has repeatedly reduced prices over the life of the platform rather than applying automatic annual increases.
C. There is no differential rate based on how a workload arrived. Charges depend on the resources consumed.
D. Consumption-based charges follow consumption. A flat workload with disciplined cleanup produces a flat bill.
36
Under the AWS shared responsibility model, which task is the responsibility of AWS?
Easy · Choose one
Explanation
Answer: D. AWS describes its half of the model as security OF the cloud: the hardware, software, networking, and facilities that run AWS Cloud services, including Regions, Availability Zones, and edge locations. Anything the customer cannot physically reach or configure sits on the AWS side of the line.
A. Identity and access management for the customer's own users and resources is squarely a customer responsibility; AWS provides IAM but never decides who in the customer's organization gets access.
B. Guest operating system patching on EC2 is explicitly named as a customer responsibility. AWS patches the underlying infrastructure, not the guest OS the customer launched.
C. Security groups are the AWS-provided firewall that the customer configures. AWS supplies the capability; deciding which ports and sources are allowed is security IN the cloud and belongs to the customer.
37
A company runs a web application on Amazon EC2 instances. Who is responsible for applying security patches to the guest operating system running on those instances?
Easy · Choose one
Explanation
Answer: D. Amazon EC2 is categorized as Infrastructure as a Service, so the customer performs the security configuration and management tasks above the hypervisor. AWS states that customers who deploy an EC2 instance are responsible for management of the guest operating system, including updates and security patches, plus any software they install and the security group configuration.
A. The source of the Amazon Machine Image does not change the boundary. AWS may publish an image, but once the instance is launched, keeping its operating system patched is the customer's job.
B. AWS maintains the software that runs the cloud infrastructure itself, such as the virtualization layer and the AWS service software, not the operating system inside a customer's instance.
C. The hypervisor isolates instances from one another; it does not reach inside a running instance to update its operating system packages.
38
Which TWO tasks are the customer's responsibility under the AWS shared responsibility model? (Choose TWO.)
Easy · Select 2 answers
Explanation
Answer: A and B. Both fall inside security IN the cloud. The customer decides who may reach their data, which is expressed through resource-based policies such as S3 bucket policies and through identity and access management. AWS supplies the mechanisms, but configuring them correctly is never delegated back to AWS.
C. Physical and environmental security of AWS facilities is an inherited control, entirely on the AWS side of the model.
D. Media decommissioning is an AWS responsibility. AWS uses documented destruction processes for storage devices so that customer data cannot be recovered from retired hardware.
E. The hypervisor is part of the infrastructure AWS operates. Customers have no access to it and no ability to patch it.
39
AWS describes certain responsibilities as shared controls, which apply to both the infrastructure layer and the customer layer but in separate contexts. Which of the following is an example AWS gives of a shared control?
Intermediate · Choose one
Explanation
Answer: D. A shared control is one where both parties carry out the same class of activity in different scopes. AWS names three: patch management, configuration management, and awareness and training. In each case AWS performs the control for its infrastructure and employees while the customer performs it for their own systems and staff.
A. Zone security and service communications protection are what AWS calls customer specific controls, based solely on the application the customer deploys. AWS performs no counterpart.
B. Physical and environmental controls are an inherited control. The customer inherits them wholly from AWS and performs no part of them.
C. Media disposal is performed only by AWS. The customer has no equivalent activity because they never possess the hardware.
40
A company migrates a self-managed MySQL database from Amazon EC2 to Amazon RDS. Which responsibility shifts from the customer to AWS as a result of this migration?
Intermediate · Choose one
Explanation
Answer: C. Amazon RDS is a managed service, and AWS states that it manages backups, software patching, automatic failure detection, and recovery. Moving up the abstraction ladder from EC2 to RDS transfers the undifferentiated maintenance of the engine and host to AWS while leaving the data and its access controls with the customer.
A. Logins and privileges inside the database are managed with the database engine's own security features, which remain the customer's responsibility on Amazon RDS.
B. Network access to a DB instance is controlled by security groups and subnet placement, both configured by the customer.
D. Encryption at rest for an RDS DB instance is a customer choice and configuration. AWS provides the capability; the customer decides whether and how to apply it.