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: how many integers between 1 and 10 ^ 16 are such that the sum of their digits is 2 ? 
Options: a ) 106 , b ) 116 , c ) 126 , d ) 136 , e ) 146

Ex Output:
d


Ex Input:
Problem: the tax on a commodity is diminished by 30 % but its consumption is increased by 15 % . find the decrease percent in the revenue derived from it ? 
Options: a ) 20 % , b ) 18 % , c ) 15 % , d ) 12 % , e ) 14 %

Ex Output:
a


Ex Input:
Problem: in a 100 - mile trip , the first 30 miles were completed at 60 mph . if the average speed for the whole trip was 40 mph , what was the average speed in the last 70 miles ? 
Options: a ) 30 mph , b ) 32 mph , c ) 35 mph , d ) 37 mph , e ) 38 mph

Ex Output:

c