Answer:
B has an immediate action so that should be imperative
Answer:
Make sure all words are spelled correctly.
Try different keywords.
Try more general keywords.
I most contexts, no. It can be considered an error if viewed from a programmer's perspective, because a bug is viewed as an error in the code of a program. If it is not viewed from a similar perspective, then it is not a synonym. Thesaurus.com can be a helpful place for you.
