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: find the area of the quadrilateral of one of its diagonals is 24 cm and its off sets 9 cm and 6 cm ?
Options: a ) 180 cm 2 , b ) 150 cm 2 , c ) 168 cm 2 , d ) 198 cm 2 , e ) 987 cm 2
Example Output: a

Example Input: Problem: the perimeter of a triangle is 42 cm and the inradius of the triangle is 5.0 cm . what is the area of the triangle ?
Options: a ) 128 cm 2 , b ) 36.0 cm 2 , c ) 105 cm 2 , d ) 25 cm 2 , e ) 135 cm 2
Example Output: c

Example Input: Problem: the volumes of two cones are in the ratio 1 : 12 and the radii of the cones are in the ratio of 1 : 3 . what is the ratio of their heights ?
Options: ['a ) a ) 3 : 4', 'b ) b ) 2 : 7', 'c ) c ) 2 : 2', 'd ) d ) 2 : 1', 'e ) e ) 2 : 9']
Example Output:
a