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'.

Example Input: Problem: if an integer n is to be selected at random from 1 to 100 , inclusive , what is probability n ( n + 1 ) will be divisible by 5 ? 
Options: a ) 1 / 5 , b ) 1 / 3 , c ) 1 / 2 , d ) 2 / 3 , e ) 2 / 5
Example Output: e

Example Input: Problem: there were 35 students in a hostel . due to the admission of 7 new students , he expenses of the mess were increased by rs . 42 per day while the average expenditure per head diminished by rs 1 . what was the original expenditure of the mess ? 
Options: a ) 125 , b ) 321 , c ) 561 , d ) 852 , e ) 420
Example Output: e

Example Input: Problem: p , q and r have rs . 9000 among themselves . r has two - thirds of the total amount with p and q . find the amount with r ? 
Options: a ) rs . 3000 , b ) rs . 3600 , c ) rs . 2400 , d ) rs . 4000 , e ) none of these
Example Output:
b