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

Example Input: Problem: the ratio of the arithmetic mean of two numbers to one of the numbers is 5 : 8 . what is the ratio of the smaller number to the larger number ? 
Options: a ) 1 : 8 , b ) 1 : 6 , c ) 1 : 5 , d ) 1 : 4 , e ) 1 : 3
Example Output: d

Example Input: Problem: x starts a business with rs . 45000 . y joins in the business after 3 months with rs . 36000 . what will be the ratio in which they should share the profit at the end of the year ? 
Options: a ) 20 : 9 , b ) 2 : 1 , c ) 3 : 2 , d ) 2 : 3 , e ) 5 : 3
Example Output: a

Example Input: Problem: in the third grade of windblown school there are 84 students , one third of them failed the math test and 1 / 6 failed that literature test . at least how many students failed both tests ? 
Options: a ) 0 . , b ) 6 . , c ) 8 . , d ) 10 . , e ) 12 .
Example Output:
a