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 bought this for my job at a swimming pool. In order to make the correct dilution of acid, I required a efficient respirator. With this particular one I was happy to find I could breathe normally and it was like there was no mask there at all. Very comfortable and efficient!!! A must buy for chemical work!

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