You are given a math word problem and you are supposed to make use of mathematical concepts like probability, combinatorics, linear equations, sequences/series, or simple operators like addition, subtraction, division, or multiplication to answer the given question. Choose the best option from the 5 given options and report that option.

Question: In a box, there are 8 red, 7 blue and 6 green balls. One ball is picked up randomly. What is the probability that it is neither red nor green?

 Option A: 1/3

 Option B: 2/5

 Option C: 3/7

 Option D: 8/27

 Option E: 9/29
Option A

Question: If x, y, and z are negative integers and 3x - 3y = -3z, then which of the following statements must be true?
I. x > y
II. x > y > z
III. x = z

 Option A: I and II

 Option B: I only

 Option C: II only

 Option D: III only

 Option E: None
Option B

Question: The markup on a necklace is 80 percent of the cost. The markup is what percent of the selling price?
(markup = selling price - cost)

 Option A:  8%

 Option B:  10%

 Option C:  44.44%

 Option D:  55%

 Option E:  66 2/3%

Option C