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: A set of numbers has the property that for any number t in the set,t+3 is in the set. If -2 is in the set, which of the following must also be in the set? I. -3 II. 1 III. 4

 Option A: I,III only

 Option B: III only

 Option C: II only

 Option D: II,III only

 Option E: I only
Option D

Question: 10 3/4 + 7 2/17 - 9 1/15=?

 Option A: 7 719/1020

 Option B: 9 817/1020

 Option C: 9 719/1020

 Option D: 8 817/1020

 Option E: None of them
Option D

Question: If a / b is an integer, which of the following statements must be true?

 Option A: q is an integer

 Option B: a = nb where n is an integer

 Option C: both a and b are integers

 Option D: b / a is an integer

 Option E: either a or b is negative

Option B