your name is epic btw.

you aren't alone in your issue - under timed conditions I almost always have about 5 questions left ... I am struggling to get any faster.

I agree. I see why A is right, but I don't see why D couldn't be true either. It provides a different explanation that to me, does not seem invalid...

Totally agree man ... the heat of the microwave heats the liquid differently, causing the pockets of heat within the liquid that a conventional source would not cause otherwise...therefore it is indeed the microwave. I understand how the other answers are wrong, but I do not understand how answer E is right.