Which combination of steps must the SysOps administrator take to meet these requirements?

Explanations:

Creating an IAM role with the CloudWatchAgentServerPolicy allows the EC2 instances to publish metrics to CloudWatch. This policy provides the necessary permissions for the CloudWatch agent to send performance data from the instances to CloudWatch.

The CloudWatchApplicationInsightsReadOnlyAccess policy is not relevant for monitoring disk utilization; it is primarily for read-only access to application insights, which does not contribute to the specific task of monitoring EBS disk utilization.

Installing and starting the CloudWatch agent is essential for gathering disk utilization metrics from the EBS volumes. The agent collects system-level metrics, which includes disk usage statistics, and sends them to CloudWatch.

While installing the CloudWatch agent is necessary, simply attaching the IAM role to the agent is not a valid approach. The IAM role must be created and assigned to the instances, which was covered in option A. The role should already include the necessary permissions when the agent is installed and started.

Configuring a CloudWatch alarm to trigger when the disk_used_percent metric exceeds 80% accurately reflects the requirement to monitor when disk utilization becomes problematic. This metric directly indicates the percentage of disk space in use.

Using the disk_used metric to set an alarm based on the absolute usage or the disk_free metric based on a percentage is less efficient and could lead to confusion. It does not directly monitor disk utilization in a clear manner as the disk_used_percent metric does. The proper metric to track for disk utilization is disk_used_percent.