In this task, you need to answer the given multiple-choice question on the general math. Classify your answers into 'a', 'b', 'c', 'd', and 'e'.

Input: Consider Input: Problem: a = 4 ^ 15 - 625 ^ 3 and a / x is an integer , where x is a positive integer greater than 1 , such that it does not have a factor p such that 1 < p < x , then how many different values for x are possible ? 
Options: a ) none , b ) one , c ) two , d ) three , e ) four

Output: c


Input: Consider Input: Problem: if x / 4 years ago roger was 14 years old and x / 4 years from now he will be 4 x years old , how old will he be 6 x years from now ? 
Options: a ) 32 , b ) 39 , c ) 30 , d ) 40 , e ) 28

Output: b


Input: Consider Input: Problem: the average marks of a class of 30 students is 40 and that of another class of 50 students is 90 . find the average marks of all the students ? 
Options: a ) 71.25 , b ) 52.9 , c ) 52.1 , d ) 52.3 , e ) 42.5


Output: a