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: find the c . i . on a sum of rs . 10000 for 6 months at 20 % per annum , interest being compounded halfyearly ? 
Options: a ) 3010 , b ) 2010 , c ) 1000 , d ) 3100 , e ) 2100
Example Output: c

Example Input: Problem: from the sale of sleeping bags , a retailer made a gross profit of 16 % of the wholesale cost . if each sleeping bag was sold for $ 28 , what was the wholesale cost per bag ? 
Options: a ) 3.0 , b ) 3.36 , c ) 24.13 , d ) 25.0 , e ) 31.36
Example Output: c

Example Input: Problem: if 85 % of 3 / 5 of a number is 36 , then the number is ? 
Options: a ) 80 , b ) 100 , c ) 70.5 , d ) 90 , e ) none of these
Example Output:
c