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'.

Input: Consider Input: Problem: at an election 2 candidates are participated and a candidate got 20 % of votes and defeated by 500 . and 10 votes are invalid . find the total polled votes ?
Options: a ) 843 , b ) 1023 , c ) 965 , d ) 413 , e ) 1245

Output: a

Input: Consider Input: Problem: a man walking at a rate of 15 km / hr crosses a bridge in 20 minutes . the length of the bridge is ?
Options: a ) 1250 m , b ) 1110 m , c ) 950 m , d ) 1000 m , e ) 1300 m

Output: d

Input: Consider Input: Problem: in a certain pond , 100 fish were caught , tagged , and returned to the pond . a few days later , 100 fish were caught again , of which 2 were found to have been tagged . if the percent of tagged fish in the second catch approximates the percent of tagged fish in the pond , what is the approximate number of fish in the pond ?
Options: a ) 400 , b ) 625 , c ) 1,250 , d ) 2,500 , e ) 10,000
Output: d