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

Input:
Switching to this prime lens from my kit lens was akin to switching from night to day.
The images are quite clear, and the results are stunning.
I'm really pleased with it.

Eventually I will switch to the USM version, but not yet.

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