In this task, you need to provide the correct option for a given problem from the provided options.

Ex Input:
Problem: the hcf of two numbers is 42 and the other two factors of their lcm are 11 and 12 . what is the largest number . 
Options: a ) 462 , b ) 450 , c ) 480 , d ) 504 , e ) 555

Ex Output:
d


Ex Input:
Problem: among 600 students , 56 % study sociology , 44 % study mathematics and 40 % study biology . if 30 % of students study both mathematics and sociology , what is the largest possible number of students who study biology but do not study either mathematics or sociology ? 
Options: a ) 30 , b ) 90 , c ) 120 , d ) 172 , e ) 180

Ex Output:
e


Ex Input:
Problem: the contents of two vessels containing copper and tin in the ratio 1 : 2 and 2 : 5 are mixed in the ratio 1 : 4 . the resulting mixture will have copper and tin in the ratio ? 
Options: a ) 15 : 32 , b ) 21 : 28 , c ) 31 : 74 , d ) 33 : 37 , e ) 41 : 92

Ex Output:

c