Teacher:In this task, you need to provide the correct option for a given problem from the provided options.
Teacher: Now, understand the problem? Solve this instance: Problem: the least whole number which when subtracted from both the terms of the ratio 6 : 7 to give a ratio less than 16 : 21 , is 
Options: a ) 3 , b ) 4 , c ) 5 , d ) 6 , e ) 7
Student:

Show your work and conclude with the exact phrasing "Therefore, the final answer is [answer]." where [answer] is just the final number or expression that solves the problem.
user
a