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:
I have been using the trackman wheel for several months now and I love it. I have arthritis and the natural design, with the track ball on the side  , lets my hand lie in a completely natural position. No reaching or stretching. The most comfortable mouse ever designed, in my humble opinion.

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