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

Ex Input:
Problem: if the radius of a circle is increased by 40 % then the area is increased by : 
Options: a ) 44 % , b ) 120 % , c ) 96 % , d ) 40 % , e ) none of the above

Ex Output:
c


Ex Input:
Problem: obra drove 200 π meters along a circular track . if the area enclosed by the circular track on which she drove is 57,600 π square meters , what percentage of the circular track did obra drive ? 
Options: a ) 6.67 % , b ) 12.5 % , c ) 41.66 % , d ) 25 % , e ) 33.3 %

Ex Output:
c


Ex Input:
Problem: in right triangle abc , ac is the hypotenuse . if ac is 10 and ab + bc = 20 , what is the area of the triangle abc ? 
Options: a ) 225 , b ) 450 , c ) 75 , d ) 200 , e ) 200 √ 2

Ex Output:

c