Sum of Even integers question, Gmat Hacks

Hi everyone, I have come across this question from gmathacks.com

Which of the following expresses the sum of the first 50 positive even integers?

A (2)(50)
B (25)(100)
C (25)(102)
D (50)(100)
E (50)(102)


The answer is C. The way I approached this question was under the assumption that zero is a positive integer.

So I figured.

The first even consecutive integer is 0 and the last one is 100. The mean would be (50). I also figured the number of terms would be 50 (since they say this is the number of terms in the question prompt). Therefore, the sum would be (50)(50)

But...The solution says

"the first even consecutive integers between 2 and 100 inclusive. The mean of those 50 umbers is equal to the median. So the mean is 51. We know there are 50 terms and the average is 51, so the sum is (50)(51)...This would then equal (25)(102)"


Question:

I do not understand why we are not counting 0 as an even integer. I though 0 was an even integer. Could someone please let me know if this is a poorly written question or if I just should not assume that 0 is an even integer on the gmat.

Thanks a lot