You wrote a map function that throws a runtime exception when it encounters a control character
in input data. The input supplied to your mapper contains twelve such characters totals, spread
across five file splits. The first four file splits each have two control characters and the last split has
four control characters.
Indentify the number of failed task attempts you can expect when you run the job with
mapred.max.map.attempts set to 4:

A.
You will have forty-eight failed task attempts

B.
You will have seventeen failed task attempts

C.
You will have five failed task attempts

D.
You will have twelve failed task attempts

E.
You will have twenty failed task attempts

Explanation:
There will be four failed task attempts for each of the five file splits.

Note:
When the jobtracker is notified of a task attempt that has failed (by the tasktracker’s heartbeat tall),
it will reschedule execution of the task. The jobtracker will try to avoid rescheduling the task on a
tasktracker where it has previously tailed. Furthermore, if a task fails four times (or more), it will
not be retried further. This value is configurable: the maximum number of attempts to run a task is
controlled by the mapred.map.max.attempts property for map tasks and
mapred.reduce.max.attempts for reduce tasks. By default, if any task fails four times (or whatever
the maximum number of attempts is configured to), the whole job fails.