Instruction: Determine the sentiment expressed by the user in her review from the provided choices, and respond by selecting one of the available options.

Input:
I use these temperature probes for my heating system and hot water tank.  The improved design enables the batteries to last longer, as the probe automatically turns off after a short period of time.  Received the probes quickly after ordering them.

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