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: the product of two positive integers is 675 and their difference is 2. what is the bigger number ?
Options: a. 21, b. 23, c. 25, d. 27, e. 29
d

Problem: a cement mixture is composed of 3 elements. by weight, 1 / 2 of the mixture is sand, 1 / 5 of the mixture is water, and the remaining 15 pounds of the mixture is gravel. what is the weight of the entire mixture in pounds ?
Options: a. 30, b. 40, c. 50, d. 60, e. 80
c

Problem: soymilk are sold in packages of two or 3 only. if hannah bought 17 soymilk exactly, what could be the number of large packs hannah bought ?
Options: a. 1, b. 4, c. 3, d. 5, e. 8

c