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: the least perfect square , which is divisible by each of 21 , 36 and 66 is
Options: a ) 213414 , b ) 213424 , c ) 213434 , d ) 213444 , e ) none of these
Example Output: d

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: the surface area of a sphere is same as the curved surface area of a right circular cylinder whose height and diameter are 6 cm each . the radius of the sphere is
Options: a ) 3 cm , b ) 4 cm , c ) 6 cm , d ) 8 cm , e ) none
Example Output:
a