Which of the following is not a search engine?

A customer's nightly EMR job processes a single 2-TB data file stored on Amazon Simple Storage Service (S3). The EMR job runs on two On-Demand core nodes and three On-Demand task nodes. Which of the following may help reduce the EMR job completion time?

A. Use three Spot Instances rather than three On-Demand instances for the task nodes. B. Change the input split size in the MapReduce job configuration. C. Use a bootstrap action to present the S3 bucket as a local filesystem. D. Launch the core nodes and task nodes within an Amazon Virtual Cloud. E. Adjust the number of simultaneous mapper tasks. F. Enable termination protection for the job flow.

In the DNS hierarchy, where is information about how to find the top-level domain servers held?

a. In the hosts file on the local machine. b. On the DNS root servers. c. On DNS caching-only servers. d. In the organization's forward lookup zone.