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: if the area of a square with sides of length 5 centimeters is equal to the area of a rectangle with a width of 4 centimeters , what is the length of the rectangle , in centimeters ? 
Options: a ) 4 , b ) 8 , c ) 12 , d ) 7 , e ) 18
Example Output: d

Example Input: Problem: a rectangular block 10 cm by 20 cm by 30 cm is cut into an exact number of equal cubes . find the least possible number of cubes ? 
Options: a ) 6 , b ) 10 , c ) 15 , d ) 40 , e ) 22
Example Output: a

Example Input: Problem: in two triangle , the ratio of the areas is 4 : 3 and that of their heights is 3 : 4 the ratio of their bases is 
Options: ['a ) 16 : 9', 'b ) 9 : 16', 'c ) 9 : 12', 'd ) 16 : 12', 'e ) 4 : 12']
Example Output:
a