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: subtracting 3 % of a from a is equivalent to multiplying a by how much ?
Options: a. 0.97, b. 9.4, c. 0.094, d. 94, e. none
[EX A]: a

[EX Q]: Problem: what least number should be added to 1057, so that the sum is completely divisible by 23
Options: a. a. 4, b. b. 1, c. c. 2, d. d. 3, e. e. 5
[EX A]: b

[EX Q]: Problem: how many bricks each measuring 22 cm x 10.25 cm x 8 cm, will be needed to build a wall 9 m x 7 m x 10.5 m
Options: a. 5600, b. 3066, c. 3055, d. 7200, e. none of these
[EX A]:
b