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: the length of a rectangle is reduced by 22 % . by what % would the width have to be increased to maintain the original area ?
Options: a ) 14 % , b ) 15 % , c ) 28 % , d ) 30 % , e ) 35 %

Ex Output:
c

Ex Input:
Problem: 34 . the side surface of a cylinder is rolled with a rectangle . if the height of a cylinder is 16 feet and the perimeter of the circular base . is 12 feet , what is the diagonal of the rectangle ?
Options: ['a ) 16', 'b ) 20', 'c ) 18', 'd ) 22', 'e ) 21']

Ex Output:
b

Ex Input:
Problem: anup manages to draw 7 circles of equal radii with their centres on the diagonal of a square such that two extreme circles touch two sides of the square and each middle circle touches two circles on either side . find the ratio of radius of the circles to the side of the square .
Options: ['a ) 1 : ( 2 + 6 ^ ( 1 / 2 ) )', 'b ) 1 : ( 4 + 7 ^ ( 1 / 3 ) )', 'c ) ( 2 + 7 ^ ( 1 / 2 ) ) : 1', 'd ) ( 2 + 7 ^ ( 1 / 2 ) ) : 2', 'e ) none of these']

Ex Output:
e