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'.

Input: Consider Input: Problem: 8 persons can build a wall 140 m long in 42 days . in how many days can 30 persons complete a similar wall 100 m long ? 
Options: a ) 12 , b ) 10 , c ) 8 , d ) 6 , e ) 5

Output: c


Input: Consider Input: Problem: the curved surface of a sphere is 64 π cm 2 . find its radius ? 
Options: ['a ) 8', 'b ) 3', 'c ) 4', 'd ) 9', 'e ) 7']

Output: c


Input: Consider Input: Problem: john left home and drove at the rate of 45 mph for 2 hours . he stopped for lunch then drove for another 3 hours at the rate of 45 mph to reach his destination . how many miles did john drive ? 
Options: a ) 235 miles . , b ) 245 miles . , c ) 225 miles . , d ) 265 miles . , e ) 275 miles .


Output: c