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

Example Input: Problem: the area of a triangle is with base 10 m and height 10 m ? 
Options: a ) 11 , b ) 10 , c ) 50 , d ) 122 , e ) 12
Example Output: c

Example Input: Problem: the length and breadth of a rectangle is increased by 10 % and 25 % respectively . what is the increase in the area ?. a . 27.5 % 
Options: ['a ) 37.2 %', 'b ) 37.5 %', 'c ) 30.2 %', 'd ) 37.7 %', 'e ) 33.2 %']
Example Output: b

Example Input: Problem: the radius of a cylindrical vessel is 7 cm and height is 3 cm . find the whole surface of the cylinder ? 
Options: ['a ) 520 sq cm', 'b ) 840 sq cm', 'c ) 440 sq cm', 'd ) 120 sq cm', 'e ) 5 sq cm']
Example Output:
c