Instruction: Determine the sentiment expressed by the user in her review from the provided choices, and respond by selecting one of the available options.

Input:
I based my purchase of this coffee maker on Consumer Reports' top rating. I had decent luck using the handy 1-4 cup setting for small batches. After a weak 12-cup batch, I decided to double the amount of ground coffee per cup, as per the coffee manufacturer's suggestion. I didn't use the 1-4 cup option since I was actually making six cups. The coffee again turned out weak. I was about to toss the grounds when I discovered that about 20-30% of them were untouched by water during the brewing process. No wonder it turned out weak. If results don't improve in the next few pots, this thing is going back to the store.

Options:
A: very positive
B: positive
C: neutral
D: negative
E: very negative
Answer: D: negative