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

[Q]: Problem: the ratio between the present ages of a and b is 4 : 3 respectively . the ratio between a ' s age 4 years ago and b ' s age 4 years hence is 1 : 1 . what is the ratio between a ' s age 4 years hence and b ' s age 4 years ago ? 
Options: a ) 3 : 4 , b ) 3 : 0 , c ) 3 : 1 , d ) 3 : 2 , e ) 9 : 5
[A]: e


[Q]: Problem: what is the prime factors ’ number of 48 ? 
Options: a ) 2 , b ) 3 , c ) 4 , d ) 5 , e ) 6
[A]: d


[Q]: Problem: one fast typist type some matter in 4 hrs and another slow typist type the same matter in 6 hrs . if both do combine in how much time they will take to finish . 
Options: a ) 10 hr , b ) 1 hr , c ) 2 hr 24 mins , d ) 3 hr 4 mins , e ) 4 hr 10 mins
[A]:
c