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.

Problem: there is one 4 - digit whole number n, such that the last 4 digits of n 2 are in fact the original number n
Options: a. 8476, b. 7376, c. 9376, d. 7378, e. 9466
c

Problem: if x 2 + kx - 3, is divisible by ( x - 1 ), what is the value of k
Options: a. - 1, b. 1, c. 2, d. - 1, e. 0
c

Problem: a placed 3 sheets with two carbons to get two extra copies of the original. then he decided to get more carbon copies and folded the paper in such a way that the upper half of the sheets were on top of the lower half. then he typed. how many carbon copies did he get ?
Options: a. 1, b. 2, c. 3, d. 4, e. 5

b