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 radius of a circle is diminished by 10 % then its area is diminished by 
Options: ['a ) 22', 'b ) 19', 'c ) 877', 'd ) 26', 'e ) 271']

Ex Output:
b


Ex Input:
Problem: a circle and a rectangle have the same perimeter . the sides of the rectangle are 18 cm and 26 cm . what is the area of the circle ? 
Options: ['a ) 88 cm 2', 'b ) 154 cm 2', 'c ) 1250 cm 2', 'd ) 616 cm 2', 'e ) none of these']

Ex Output:
d


Ex Input:
Problem: a cube has a volume of 216 cubic feet . if a similar cube is twice as long , twice as wide , and twice as high , then the volume , in cubic feet of such cube is ? 
Options: a ) 24 , b ) 1728 , c ) 64 , d ) 80 , e ) 100

Ex Output:

b