Bizarre question. My reaction after reading both (1) and (2) was "Ok...
Divisibility by 6 needs divisibility by 2 AND 3. Also, the sum needs to be even.
(1) says nothing, really. If the least number is odd, we know of the other two numbers one is odd and one is even. However, this doesn't tell us anything about divisibility. Insufficient.
(2) also says nothing, amazingly. If the greatest number is odd, we know of the other two numbers one is odd and one is even. However, this doesn't tell us anything about divisibility. Insufficient.
(1) and (2) together are useless too. So E is correct.
There is NO information in either (1) and (2) any properties of the numbers which might imply divisibility. Generally, you need something to establish the property of the set like spacing, prime or not, correlation between numbers in a part of the set etc to say anything about divisibility. I hope you didn't miss typing out a key term like consecutive or evenly spaced etc.
I have no idea where you got this question from, but either:
(1) I am high on sleep deprivation and cant read basic text straight.
(2) You need to look at a better compendium of questions, no offense.
The only ability the GMAT is an indicator of...is the ability to do well on the GMAT.