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: how many 4 x 4 x 4 cubes could fit in a 9 x 13 x 16 box ?
Options: a ) 22 , b ) 28 , c ) 29 , d ) 31 , e ) 32
Example Output: c

Example Input: Problem: find the smallest number that should be multiplied with 54000 to make it a perfect cube .
Options: ['a ) 4', 'b ) 5', 'c ) 6', 'd ) 3', 'e ) 7']
Example Output: a

Example Input: Problem: a cube of edge 6 cm is cut into cubes each of edge 1 cm . the ratio of the total surface area of one of the small cubes to that of the large cube is equal to :
Options: a ) 1 : 25 , b ) 1 : 36 , c ) 1 : 52 , d ) 1 : 522 , e ) none
Example Output:
b