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've been using these for over five years.  I know how long cause I got them my first month at my after-college job.  They sound nice.  I am not an audiophile, but I know they are well-received for their flat, true output and I am certainly happy.  They do crush my head and I can only get by for an hour without a break.

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