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 smallest number which when diminished by 2, is divisible by 12, 16, 18, 21 and 28 is
Options: a. 1008, b. 1010, c. 1022, d. 1032, e. 1043
[EX A]: b

[EX Q]: Problem: 1391 x 1391 = ?
Options: a. a. 1951609, b. b. 1951601, c. c. 1951602, d. d. 1951603, e. e. 1934881
[EX A]: e

[EX Q]: Problem: a shipment of 240 smartphones contains 84 that are defective. if a customer buys two smartphones at random from the shipment, what is the approximate probability that both phones are defective ?
Options: a. 1 / 250, b. 9 / 74, c. 1 / 11, d. 1 / 9, e. 1 / 3
[EX A]:
b