Explanation
Answer - C
This is given in the AWS Documentation
list-stack-resources
Description
Returns descriptions of all resources of the specified stack.
For deleted stacks, ListStackResources returns resource information for up to 90 days after the stack has been
deleted.
See also: AWS API Documentation
See 'aws help' for descriptions of global parameters.
list-stack-resources is a paginated operation. Multiple API calls may be issued in order to retrieve the entire
data set of results. You can disable pagination by
providing the -no-paginate argument. When using -output text and the -query argument on a paginated
response, the -query argument must extract data from
the results of the following query expressions: StackResourceSummaries
For more information on the CLI command, please visit the below URL:
http://docs.aws.amazon.com/cli/latest/reference/cloudformation/list-stack-resources.
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The default maximum number of Roles per AWS account is 250.
Reference: http://docs.aws.amazon.com/IAM/latest/UserGuide/LimitationsOnEntities.htm

Explanation
Clastic Load Balancing provides access logs that capture detailed information about requests sent to your load
balancer. Cach log contains information such as the
time the request was received, the client's IP address, latencies, request paths, and server responses. You can
use these access logs to analyze traffic patterns and
to troubleshoot issues.
Option A is invalid because this service will monitor all AWS services
Option C and D are invalid since CLB already provides a logging feature.
For more information on ELB access logs, please refer to the below document link: from AWS
* http://docs.aws.amazon.com/elasticloadbalancing/latest/classic/access-log-collection.
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