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: on my sister ' s birthday , she was 132 cm in height , having grown 10 % since the year before . how tall was she the previous year ? 
Options: a ) 130 cm , b ) 126 cm , c ) 120 cm , d ) 116 cm , e ) 112 cm

Ex Output:
c


Ex Input:
Problem: a rectangular plot measuring 10 meters by 50 meters is to be enclosed by wire fencing . if the poles of the fence are kept 5 meters apart . how many poles will be needed ? 
Options: a ) 46 m , b ) 66 m , c ) 26 m , d ) 24 m , e ) 25 m

Ex Output:
d


Ex Input:
Problem: a and b together can do a work in 7 days . if a alone can do it in 56 days . in how many days can b alone do it ? 
Options: a ) 11 , b ) 8 , c ) 21 , d ) 20 , e ) 25

Ex Output:

b