In this task, you need to answer the given multiple-choice question on the general math. Classify your answers into 'a', 'b', 'c', 'd', and 'e'.

Ex Input:
Problem: in a renowned city , the average birth rate is 6 people every two seconds and the death rate is 3 people every two seconds . estimate the size of the population net increase that occurs in one day . 
Options: a ) 129,500 , b ) 129,600 , c ) 129,700 , d ) 129,800 , e ) 129,900

Ex Output:
b


Ex Input:
Problem: if the charge of staying in a student youth hostel $ 18.00 / day for the first week , and $ 14.00 / day for each additional week , how much does it cost to stay for 23 days ? 
Options: a ) $ 160 , b ) $ 350 , c ) $ 282 , d ) $ 274 , e ) $ 286

Ex Output:
b


Ex Input:
Problem: if a : b : : 3 : 4 , then what is ( 5 a + 6 b ) : ( a - 2 b ) ? 
Options: a ) 57 : 11 , b ) - 57 : 11 , c ) 11 : 10 , d ) - 39 : 5 , e ) - 1 : 10

Ex Output:

d