You will be given a definition of a task first, then some input of the task.
In this task, you need to provide the correct option for a given problem from the provided options.

Problem: in 50 l can , milk and water in the ratio of 3 : 1 . if the ratio has made 1 : 3 then the quantity of water that has to be added further is ?
Options: a ) 100 , b ) 120 , c ) 90 , d ) 80 , e ) 70
Output:
a