If you encounter the error message "A Git process may have crashed in this repository. Remove the file manually to continue," which file is typically referenced and how should you handle it?
a. Remove the .git/refs/heads/ file that is causing the issue.
b. Delete the .git/index.lock file to resolve the problem.
c. Clear the .git/config file and reconfigure your repository settings.
d. Erase the .git/HEAD file to reset the repository.