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

Ex Input:
Problem: hree number are in the ratio of 3 : 4 : 5 and their l . c . m . is 2400 . their h . c . f . is : 
Options: a ) 40 , b ) 50 , c ) 60 , d ) 70 , e ) 80

Ex Output:
a


Ex Input:
Problem: two vessels contains equal number of mixtures milk and water in the ratio 4 : 2 and 5 : 1 . both the mixtures are now mixed thoroughly . find the ratio of milk to water in the new mixture so obtained ? 
Options: a ) 3 : 1 , b ) 9 : 13 , c ) 5 : 11 , d ) 11 : 3 , e ) 15 : 4

Ex Output:
a


Ex Input:
Problem: how many positive factors do 150 and 90 have in common ? 
Options: a ) 8 , b ) 12 , c ) 16 , d ) 18 , e ) 24

Ex Output:

a