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 trackball was a gift and I enjoyed it very much, exept that you have to clean it often and the (rollers?) don't last very long. Within a year I had to replace the mouse.

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