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: if 45 - [ 28 - { 37 - ( 15 - * ) } ] = 59 , then * is equal to : 
Options: a ) - 29 , b ) - 19 , c ) 20 , d ) 29 , e ) 39

Ex Output:
c


Ex Input:
Problem: whats the reminder when 879,548 , 521,456 , 258,759 , 653,258 , 778,455 , 658,985 is divided by 4 
Options: a ) 1 , b ) 7 . , c ) 2 . , d ) 3 , e ) 9

Ex Output:
a


Ex Input:
Problem: a batsman had a certain average of runs for 16 innings . in the 17 th innings , he made a score of 87 runs thereby increasing his average by 3 . what is his average after 17 innings ? 
Options: a ) 39 , b ) 88 , c ) 266 , d ) 278 , e ) 221

Ex Output:

a