Instruction: Given the user's review, identify the user's sentiment from the listed options. Answer using one of the options.

Input:
I purchased this knife for my teenage son as an "upgrade" to an older, simpler model.  He absolutely loves it and carries it everywhere.  I'm extremely satisfied.

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