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'.

Example Input: Problem: if a : b = 2 : 3 , b : c = 4 : 5 and c : d = 5 : 9 then a : d is equal to :
Options: a ) 11 : 17 , b ) 8 : 27 , c ) 5 : 9 , d ) 2 : 9 , e ) none
Example Output: b

Example Input: Problem: $ 350 is divided among a , b , and c so that a receives half as much as b , and b receives half as much as c . how much money is c ' s share ?
Options: a ) $ 200 , b ) $ 225 , c ) $ 250 , d ) $ 275 , e ) $ 300
Example Output: c

Example Input: Problem: if one person completes a journey in 10 hrs . he travels 1 st half of the journey at the rate of 21 km / hr and 2 nd half at therate of 24 km / hr . find the total journey in km .
Options: a ) 200 km , b ) 212 km , c ) 224 km , d ) 230 km , e ) 256 km
Example Output:
c