If a, b, c are consecutive positive integers and b<a<c, which of the following must be true?
I. c-b=2
II. abc is an even integer
III. (a+b+c)/3 is an integer  Select:
A) I	B) II	C) I and II	D) II and III	E) I, II and III
1. c-b=2 --&gt; b, a, c are consequitive positive integers and a&lt;b&lt;c then c=b+2 --&gt; c-b=2. So this statement is always true;   2. abc is an even integer --&gt; out of any 3 consecutive integers at least one must be even thus abc=even. So this statement is also always true;   3. (a+b+c)/4 is an integer --&gt; the sum of odd number of consecutive integers is ALWAYS divisible by that odd number. Or: (a+b+c)/4=fraction.   Answer: I and II.
<result>C</result>
If a, b, c are consecutive positive integers and b<a<c, which of the following must be true?
I. c-b=2
II. abc is an even integer
III. (a+b+c)/3 is an integer