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

Input: Consider Input: Problem: if the radius of a circle is decreased 20 % , what happens to the area ? 
Options: a ) 10 % decrease , b ) 20 % decrease , c ) 36 % decrease , d ) 40 % decrease , e ) 50 % decrease

Output: c


Input: Consider Input: Problem: the largest four - digit number which is a perfect cube , is 
Options: ['a ) 8000', 'b ) 9261', 'c ) 9999', 'd ) none of these', 'e ) can not be determined']

Output: b


Input: Consider Input: Problem: what is the length of the diagonal of a square whose area is 4 times of another square with diagonal as 5 v 2 cm ? 
Options: ['a ) 20 v 2', 'b ) 10', 'c ) 10 v 2', 'd ) 20', 'e ) 25']


Output: c