If a, b, c are consecutive positive integers and a<b<c, which of the following must be true?
I. c-a=2
II. abc is an even integer
III. a-b is positive integer  Select the correct option:	A) I	B) II	C) I and II	D) II and III	E) I, II and III
If a, b, c are consequitive positive integers and a&lt;b&lt;c, which of the following must be true?   1. c-a=2   2. abc is an even integer   3. (a+b+c) is an integer   1.   a=a   b=a+1   c=a+2   c-a=a+2-a=2.   Correct   2. abc   a can be either even or odd   if a=even; abc=even;   if a=odd,b=even; abc=even   Rule:   multiple of any number of integers if atleast once multiplied by an even number will result in even.   even*even=even   even*odd=even   Correct   3. a-b = 1-2 = -1 =&gt; negative   Answer : I and II
<result>C</result>
If a, b, c are consecutive positive integers and a<b<c, which of the following must be true?
I. c-a=2
II. abc is an even integer
III. a-b is positive integer