An AWS Lambda function accesses two Amazon DynamoDB tables. A developer wants to improve the performance of the Lambda function by identifying bottlenecks in the function.
How can the developer inspect the timing of the DynamoDB API calls?

A. Add DynamoDB as an event source to the Lambda function. View the performance with Amazon CloudWatch metrics.
B. Place an Application Load Balancer (ALB) in front of the two DynamoDB tables. Inspect the ALB logs.
C. Limit Lambda to no more than five concurrent invocations. Monitor from the Lambda console.
D. Enable AWS X-Ray tracing for the function. View the traces from the X-Ray service.