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: a hall is 24 meters long and 12 meters wide . if the sum of the areas of the floor and the ceiling is equal to the sum of the areas of four walls , what is the volume of the hall ( in cubic meters ) ? 
Options: ['a ) 1896', 'b ) 1912', 'c ) 2108', 'd ) 2304', 'e ) 2524']

Ex Output:
d


Ex Input:
Problem: two equal triangles constitute rhombus a . if the diagonals of rhombus are 15 cm and 20 cm long . what is the area of each triangle ? 
Options: ['a ) 300', 'b ) 150', 'c ) 75', 'd ) 40', 'e ) 20']

Ex Output:
c


Ex Input:
Problem: find the smallest number which should be multiplied with 520 to make it a perfect square . 
Options: a ) 30 , b ) 120 , c ) 55 , d ) 35 , e ) none of these

Ex Output:

e