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:
It works but there seems to be a small amount of rust forming in the bottom of the water chamber.  Is it supposed to be like this?

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