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 square is equal to five times the area of a rectangle of dimensions 20 cm * 16 cm . what is the perimeter of the square ?
Options: a ) 289 cm , b ) 160 cm , c ) 829 cm , d ) 288 cm , e ) 289 cm
Example Output: b

Example Input: Problem: 36 people { a 1 , a 2 , . . . , a 36 } meet and shake hands in a circular fashion . in other words , there are totally 36 handshakes involving the pairs , { a 1 , a 2 } , { a 2 , a 3 } , . . . , { a 35 , a 36 } , { a 36 , a 1 } . then size of the smallest set of people such that the rest have shaken hands with at least one person in the set is
Options: ['a ) 11', 'b ) 12', 'c ) 13', 'd ) 15', 'e ) 18']
Example Output: b

Example Input: Problem: a cube of edge 6 cm is cut into cubes each of edge 3 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 : 4 , b ) 1 : 25 , c ) 1 : 52 , d ) 1 : 522 , e ) none
Example Output:
a