Obviously there are at least as many reasons to downvote you as the number of downvotes you got, but I don't think adding E would've saved you from any of them, since you'd still be the one preselecting A-D.

Maybe you thought it would be as simple as people replying "B" or "C", but nobody just picked one of the answers and you got a super long reply that must have taken a long time to type out. The effort for a quick vote vs. writing a comment is heavily skewed towards voting.

You got some high-effort replies to your question anyway, so maybe just ignore the low-effort votes.