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:
They're OK, but wouldn't buy them again. The rear sight is made sloppy, tighten it up and won't adjust low enough on my buckmark. Factory sent me another, but it was no better. Independent vendor wouldn't publish my less than stellar review, so i won't do business with the again based on their sensored product reviews. Will keep the fron sight, but the original rear sight was far more accurate.

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