Excluding stoppages, the speed of a bus is 50 kmph and including stoppages, it is 43 kmph. For how many minutes does the bus stop per hour?  Choose the correct choice from the following options:
A) 70 min  B) 16 min  C) 20 min  D) 8.4 min  E) 40 min

Rationale: "d 8.4 min due to stoppages , it covers 7 km less . time taken to cover 9 km = ( 7 / 50 x 60 ) min = 8.4 min"
Answer: D