The . . . . . . . . as just the value field append(value) and the key is a LongWritable that contains the record number, count + 1.

A. Defines how input data is read B. Defines the map output format C. Defines the reduce output format D. Defines the partitioning logic

A. Manages computation resources B. Reads and parses input data C. Executes MapReduce jobs D. Manages Hadoop ecosystem tools

A. Manage storage layer B. Manage computation resources C. Execute MapReduce jobs D. Manage Hadoop ecosystem tools

A. Combine intermediate key-value pairs on the mapper side B. Distribute data to reducers C. Aggregate values on the reducer side D. Sort and shuffle data