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: if a / b = 1 / 3, b / c = 2, c / d = 1 / 2, d / e = 3 and e / f = 1 / 10, then what is the value of abc / def ?
Options: a. 27 / 4, b. 27 / 8, c. 3 / 4, d. 3 / 20, e. 1 / 4
[A]: d


[Q]: Problem: find the cost of fencing around a circular field of diameter 32 m at the rate of rs. 2 a meter ?
Options: a. 201, b. 132, c. 772, d. 592, e. 261
[A]: a


[Q]: Problem: a factory produces 6400 toys per week. if the workers at this factory work 3 days a week and if these workers make the same number of toys everyday, how many toys are produced each day ?
Options: a. 1375 toys, b. 2133 toys, c. 3375 toys, d. 4375 toys, e. 5375 toys
[A]:
b