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'.

Ex Input:
Problem: what annual payment will discharge a debt of rs . 1030 due in 2 years at the rate of 5 % compound interest ? 
Options: a ) 553.94 , b ) 551.25 , c ) 534.33 , d ) 543.33 , e ) 646.33

Ex Output:
a


Ex Input:
Problem: the value of a machine depreciates at 20 % per annum . if its present value is rs . 1 , 50,000 , at what price should it be sold after two years such that a profit of rs . 24,000 is made ? 
Options: a ) 328897 , b ) 120000 , c ) 877888 , d ) 277768 , e ) 188871

Ex Output:
b


Ex Input:
Problem: a sum of money at simple interest amounts to $ 815 in 3 years and to $ 854 in 4 years . the sum is : 
Options: a ) $ 153 , b ) $ 698 , c ) $ 398 , d ) $ 549 , e ) $ 675

Ex Output:

b