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: a distributor sells a product through an online store , which take a commission of 20 % of the price set by the distributor . the distributor obtains the product from a producer at the price of $ 18 per item . what is the price that the buyer observers online if the distributor wants to maintain a 20 % profit on the cost of the item ?
Options: a ) $ 25 , b ) $ 26 , c ) $ 27 , d ) $ 28 , e ) $ 29

Ex Output:
c

Ex Input:
Problem: the interest on a certain deposit at 4.5 % p . a . is rs . 405 in one year . how much will the additional interest in one year be on the same deposit at 5 % p . a . ?
Options: a ) rs . 50 , b ) rs . 45 , c ) rs . 40.5 , d ) rs . 48.5 , e ) rs . 49.5

Ex Output:
b

Ex Input:
Problem: a shopkeeper sold an article at $ 100 with 40 % profit . then find its cost price ?
Options: a ) $ 120 , b ) $ 100 , c ) $ 91 , d ) $ 71 , e ) $ 69

Ex Output:
d