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

Example Input: Problem: how many prime numbers between 1 and 100 are factors of 67830 ? 
Options: a ) 4 , b ) 5 , c ) 6 , d ) 3 , e ) 2
Example Output: c

Example Input: Problem: 210 students were asked in a survey if they preferred windows or mac brand computers . 60 students claimed that they preferred mac to windows brand computers . one third as many of the students who preferred mac to windows , equally preferred both brands . 90 of the students had no preference . how many of the students in the survey preferred windows to mac brand computers ? 
Options: a ) 25 , b ) 40 , c ) 50 , d ) 60 , e ) 75
Example Output: b

Example Input: Problem: among 200 students , 56 % study sociology , 44 % study mathematics and 40 % study biology . if 30 % of students study both mathematics and sociology , what is the largest possible number of students who study biology but do not study either mathematics or sociology ? 
Options: a ) 60 , b ) 90 , c ) 120 , d ) 172 , e ) 188
Example Output:
a