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: from an island , it is possible to reach the mainland by either ferry p or ferry q . ferry p travels for 3 hours at 6 kilometers per hour , while ferry q takes a route that is three times longer . if ferry p is slower than ferry q by 3 kilometers per hour , how many hours longer is the journey of ferry q compared with the journey of ferry p ? 
Options: a ) 1 , b ) 2 , c ) 3 , d ) 4 , e ) 5

Ex Output:
c


Ex Input:
Problem: find the area of trapezium whose parallel sides are 28 cm and 18 cm long , and the distance between them is 15 cm . 
Options: a ) 227 , b ) 299 , c ) 345 , d ) 161 , e ) 212

Ex Output:
c


Ex Input:
Problem: a salt solution contains 15 grams of salt per 1000 cubic centimeters of solution . if 25 cubic centimeters of the solution were poured into an empty container , how many grams of salt would be in the container ? 
Options: ['a ) 0.550', 'b ) 0.350', 'c ) 0.450', 'd ) 0.700', 'e ) 0.375']

Ex Output:

e