Answer - D
The AWS Documentation mentions the following
The Ganglia open source project is a scalable, distributed system designed to monitor clusters and grids while minimizing the impact on their performance. When you enable Ganglia on your cluster, you can generate reports and view the performance of the cluster as a whole, as well as inspect the performance of individual node instances. Ganglia is also configured to ingest and visualize Hadoop and Spark metrics
Option A is invalid because this tool is used to create and share documents that contain live code, equations, visualizations, and narrative text
Option B is invalid because this tool is used as a workflow scheduler to manage and coordinate Hadoop jobs
Option C is invalid because this tool is used for transferring data between Amazon S3, Hadoop, HDFS, and RDBMS databases
For more information on EMR Ganglia, please refer to the below URL
https://docs.aws.amazon.com/emr/latest/ReleaseGuide/emr-ganglia.html