Given a math problem with context and a question and 5 answer choices, the task is to provide the correct answer choice based on the problem. You must choose one of the given answer choices by letter: a, b, c, d, or e; anything else is invalid.

[Q]: Problem: a gardener grows cabbages in her garden that is in the shape of a square. each cabbage takes 1 square feet of area in her garden. this year, she has increased her output by 193 cabbages as compared to last year. the shape of the area used for growing the cabbages has remained a square in both these years. how many cabbages did she produce this year ?
Options: a. 8,208, b. 9,409, c. 11,424, d. 12,586, e. can not be determined
[A]: b

[Q]: Problem: in n is a positive integer less than 200, and 14 n / 60 is an integer, then n has how many different positive prime factors s ?
Options: a. 2, b. 3, c. 5, d. 6, e. 8
[A]: b

[Q]: Problem: the sum of the present ages of a father and his son is 42 years. 6 years ago, father ' s age was 4 times the age of the son. after 6 years, son ' s age will be :
Options: a. 14, b. 16, c. 18, d. 20, e. 22
[A]:
c