Whatever questions I have a question mark by, I'm not sure of my given answer. But, don't trust my answer even if I don't have a question mark next to it. Not sure if I answered your question accordingly.
1. B. hence
2. A. therefore
3. C. consequently
4. A. hence
5. ? A. therefore
6. ? C. nonetheless
7. ? C. however
8. ? B. consequently