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

Input: Consider Input: Problem: a can contains a mixture of liquids a and b is the ratio 7 : 5 . when 3 litres of mixture are drawn off and the can is filled with b , the ratio of a and b becomes 7 : 9 . how many liter of liquid a was contained by the can initially ? 
Options: a ) 7 , b ) 10 , c ) 12 , d ) 14 , e ) 16

Output: a


Input: Consider Input: Problem: income and expenditure of a person are in the ratio 5 : 4 . if the income of the person is rs . 18000 , then find his savings ? 
Options: a ) rs . 3600 , b ) rs . 3629 , c ) rs . 3279 , d ) rs . 3629 , e ) rs . 3283

Output: a


Input: Consider Input: Problem: two whole numbers whose sum is 24 is the ratio 
Options: a ) 1 : 3 , b ) 2 : 8 , c ) 1 : 6 , d ) 2 : 3 , e ) 2 : 5


Output: a