In this task, you need to answer the given multiple-choice question on the physics. Classify your answers into 'a', 'b', 'c', 'd', and 'e'.

Ex Input:
Problem: if 8 people take an hour to complete a piece of work , then how long should 16 people will take to complete the same piece of work ? 
Options: a ) 15 min , b ) 30 min , c ) 26 min , d ) 28 min , e ) 18 min

Ex Output:
b


Ex Input:
Problem: a crow leaves its nest , and flies back and forth from its nest to a nearby ditch to gather worms . the distance between the nest and the ditch is 100 meters . in one and a half hours , the crow manages to bring worms to its nest 15 times . what is the speed of the crow in kilometers per hour ? 
Options: a ) 1 , b ) 2 , c ) 3 , d ) 5 , e ) 7

Ex Output:
d


Ex Input:
Problem: walking at the rate of 8 kmph a man cover certain distance in 4 hr 45 min . running at a speed of 19 kmph the man will cover the same distance in . 
Options: a ) 100 min , b ) 110 min , c ) 140 min , d ) 120 min , e ) 150 min

Ex Output:

d