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 train of 25 carriages, each of 60 meters length, when an engine also of 60 meters length is running at a speed of 60 kmph. in what time will the train cross a bridge 1.0 km long ?
Options: a. 2.5, b. 3, c. 5, d. 7, e. 9
[A]: a

[Q]: Problem: ( ( - 1.9 ) ( 0.6 ) ( 2.6 ) ( 1.2 ) ) / 2.0 = ?
Options: a. - 0.71, b. - 2.13, c. 1.07, d. 1.71, e. 2.71
[A]: b

[Q]: Problem: if | 20 x - 10 | = 130, then find the product of the values of x ?
Options: a. - 45, b. 50, c. - 42, d. 35, e. - 30
[A]:
c