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.

[EX Q]: Problem: the total age of a and b is 16 years more than the total age of b and c. c is how many year younger than
Options: a. 14 years, b. 12 years, c. 56 years, d. 16 years, e. 55 years
[EX A]: d

[EX Q]: Problem: a man can row upstream at 25 kmph and downstream at 55 kmph, and then find the speed of the man in still water ?
Options: a. 65, b. 40, c. 30, d. 78, e. 38
[EX A]: b

[EX Q]: Problem: if 3 a – 3 b – 2 c = 32 and √ 3 a - √ ( 2 b + 2 c. = 4, what is the value of a + b + c ?
Options: a. 3, b. 9, c. 10, d. 12, e. 14
[EX A]:
c