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

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: a ratio between two numbers is 4 : 5 and their l . c . m . is 200 . the first number is 
Options: a ) 60 , b ) 40 , c ) 20 , d ) 15 , e ) none
Example Output: b

Example Input: Problem: a certain car dealership sells economy cars , luxury cars , and sport utility vehicles . the ratio of economy to luxury cars is 5 : 3 . the ratio of economy cars to sport utility vehicles is 4 : 3 . what is the ratio of luxury cars to sport utility vehicles ? 
Options: a ) 12 : 15 , b ) 8 : 9 , c ) 3 : 2 , d ) 2 : 3 , e ) 1 : 2
Example Output:
a