Answer:
file subversion
Step-by-step explanation:
File subversion is compliant with the copy-modify-and merge model. Here, users make personal working copies which they can adjust concurrently. After the adjustments, the files are merged into a final copy by the version control system or someone.
This is similar to the version control process of Leslie's company. The team members all save their altered versions of the files which are then finally merged into one final file.