Given the task definition, example input & output, solve the new input case.
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: Problem: if the sides of a triangle are 20 cm , 12 cm and 16 cm , what is its area ? 
Options: a ) 70 , b ) 79 , c ) 85 , d ) 96 , e ) 92
Output: d
"Based on the pythagorean theorem, the triangle with sides 20 cm, 12 cm and 16 cm is right angled, where the hypotenuse is 20 cm. area of the triangle = 1 / 2 * 12 * 16 = 96 cm 2 answer : option d"

New input case for you: Problem: the area of a triangle is with base 3 m and height 10 m ? 
Options: a ) 88 m 2 , b ) 10 m 2 , c ) 66 m 2 , d ) 15 m 2 , e ) 31 m 2
Output:
c