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

Q: Problem: kelly and chris are moving into a new city . both of them love books and thus packed several boxes with books . if chris packed 60 % of the total number of boxes , what was the ratio of the number of boxes kelly packed to the number of boxes chris packed ? 
Options: a ) 4 / 3 , b ) 2 / 3 , c ) 1 / 3 , d ) 3 / 4 , e ) 1 / 4

A: b
****
Q: Problem: how many kilograms of pure water is to be added to 100 kilograms of a 30 % saline solution to make it a 10 % saline solution . 
Options: a ) 100 , b ) 200 , c ) 300 , d ) 400 , e ) 500

A: b
****
Q: Problem: sandy is younger than molly by 8 years . if their ages are in the respective ratio of 7 : 9 , how old is molly ? 
Options: a ) 18 , b ) 27 , c ) 36 , d ) 45 , e ) 54

A:
c
****