Is the answer D?
This was my approach:
This is a yes/no question
Since the question is asking if a, b, and c are consecutive integers and we know that a<b<c... test the equation using:
1/a = 1/(a+1)+ 1/(a+2)
Without even solving, you can see pretty quickly that this is going to be a cubed polynomial and it won't yield an integer solution. Since it's given that a, b, and c have to be positive integers...then it follows that for this statement to be true, a, b and c cannot be consecutive integers. sufficient.
plug in the same variables from statement 1.
again, consecutive integers will not yield a positive integer for a, b, or c. Variables a, b, and c cannot be consecutive integers, so sufficient.
Since statement 1 and 2 are sufficient, ans should be D
Focused GMAT Prep