In which scenario will the change history structure be more branched: when using git rebase or git merge?

The structure of the change history will be more branched when using git merge.

Explanation:

• git merge combines branches, preserving all commits and creating a new merge commit. This results in additional branches and merges in the history.
• git rebase rewrites history by moving commits from one branch onto another, making the history more linear and clean, without additional merge commits.

Thus, if a clean and linear history is important, rebase is used, and if preserving all branches and merge context is important — merge.