Your vote is part of a signal. It is unfortunate that one cannot simultaneously signal "I don't like the B option" without also signaling "I'm okay with the A option" when there are practically 2 options + abstaining.

Nevertheless, you should think on the margin - the people most likely to skip voting for B are the people who dislike B the most and are okay with A the most, and will probably not be swayed by the usual argumetns. If anything, they're part of the reason they'll skip.