In this task, you need to answer the given multiple-choice question on the gain. Gain is the value by which to multiply the input. Classify your answers into 'a', 'b', 'c', 'd', and 'e'.

Example Input: Problem: alex takes a loan of $ 5,000 to buy a used truck at the rate of 2 % simple interest . calculate the annual interest to be paid for the loan amount . 
Options: a ) 100 , b ) 150 , c ) 720 , d ) 200 , e ) 750
Example Output: a

Example Input: Problem: vijay sells a cupboard at 10 % below cost price . had he got rs . 1500 more , he would have made a profit of 10 % . what is the cost price of the cupboard ? 
Options: a ) 7450 , b ) 7500 , c ) 7400 , d ) 7500 , e ) none of these
Example Output: b

Example Input: Problem: on selling 11 balls at rs . 720 , there is a loss equal to the cost price of 5 balls . the cost price of a ball is : 
Options: a ) s . 45 , b ) s . 50 , c ) s . 55 , d ) s . 60 , e ) s . 120
Example Output:
e