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: the profit earned by selling an article for $ 832 is equal to the loss incurred when the same article is sold for $ 448 . what should be the sale price for making 35 % profit ? 
Options: a ) $ 480 , b ) $ 450 , c ) $ 960 , d ) $ 864 , e ) $ 660
Example Output: d

Example Input: Problem: alex takes a loan of $ 4,000 to buy a used truck at the rate of 6 % simple interest . calculate the annual interest to be paid for the loan amount . 
Options: a ) 680 , b ) 700 , c ) 240 , d ) 620 , e ) 260
Example Output: c

Example Input: Problem: there were two candidates in an election . winner candidate received 70 % of votes and won the election by 280 votes . find the number of votes casted to the winning candidate ? 
Options: a ) 228 , b ) 744 , c ) 490 , d ) 199 , e ) 231
Example Output:
c