Instruction: Carefully assess the user's review for any strong expressions of sentiment, either positive or negative. Based on your analysis, select the most fitting sentiment option from the provided list as output.

Input:
I've used it only a few times and washed it every time.  I don't know why the material holds bacteria and produces an odor.  I also air dry or put it in dryer.  I mean this is on my knees not my feet yet it accumulate odor.  I do like the gel padding but maybe I will look for another product with different material.

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