Correct option is A
Given:
Mr. Becks starts from Point A and drives 9 km towards the East.
He then takes a right turn, drives 16 km, turns right and drives 28 km.
He then takes a right turn and drives 21 km.
He takes a final right turn, drives 19 km and stops at Point P.
From the given information path diagram will be.

21 - 16 = 5km
He far 5km and towards South direction should he drive in order to reach Point A again.
Thus, correct option is (a).