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

Example Input: Problem: the ratio of incomes of two person p 1 and p 2 is 5 : 4 and the ratio of their expenditures is 3 : 2 . if at the end of the year , each saves rs . 2000 , then what is the income of p 1 ? 
Options: a ) s . 5000 , b ) s . 2400 , c ) s . 4000 , d ) s . 3200 , e ) s . 4200
Example Output: a

Example Input: Problem: in township k , 1 / 5 of the housing units are equipped with cable television . if 1 / 10 of the housing units , including 1 / 3 of those that are equipped with cable television , are equipped with videocassette recorders , what fraction of the housing units have neither cable television nor videocassette recorders ? 
Options: a ) 23 / 30 , b ) 11 / 15 , c ) 7 / 10 , d ) 1 / 6 , e ) 2 / 15
Example Output: a

Example Input: Problem: what is the sum of all the prime factors of 220 and 330 ? 
Options: a ) 15 , b ) 21 , c ) 35 , d ) 41 , e ) 64
Example Output:
d