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:
This is the best knife sharpener I've ever used.  Simple, easy to use, works well and above all, it puts a razor edge on flat blade knives that hold that edge quite a while.

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