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: a lady builds 8 cm length , 15 cm width , and 5 cm height box using 10 cubic cm cubes . what is the minimum number of cubes required to build the box ? 
Options: a ) 107 , b ) 60 , c ) 70 , d ) 89 , e ) 78
Example Output: b

Example Input: Problem: one side of a rectangle is 3 cm shorter than the other side . if we increase the length of each side by 1 cm , then the area of the rectangle will increase by 16 cm 2 . find the lengths of all sides . 
Options: a ) 10 and 3 , b ) 9 and 6 , c ) 10 and 7 , d ) 3 and 10 , e ) 10 and 10
Example Output: b

Example Input: Problem: what is the measure of the angle y made by the diagonals of the any adjacent sides of a cube . 
Options: a ) 30 , b ) 45 , c ) 60 , d ) 75 , e ) 90
Example Output:
c