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: a car is purchased on hire - purchase . the cash price is $ 26 000 and the terms are a deposit of 10 % of the price , then the balance to be paid off over 60 equal monthly installments . interest is charged at 12 % p . a . what is the monthly installment ? 
Options: a ) $ 603 , b ) $ 624 , c ) $ 625 , d ) $ 626 , e ) $ 627
Example Output: b

Example Input: Problem: if a radio is purchased for rs 490 and sold for rs 465.50 find the loss % ? 
Options: a ) 5 % , b ) 4 % , c ) 6 % , d ) 8 % , e ) 7 %
Example Output: a

Example Input: Problem: running at the same constant rate , 8 identical machines can produce a total of 240 pens per minute . at this rate , how many pens could 5 such machines produce in 5 minutes ? 
Options: a ) 114 , b ) 108 , c ) 192 , d ) 750 , e ) 777
Example Output:
d