Donna has been developing software for her company. she makes a copy of the directory where her code is stored each time she makes a significant change. however, the project she started years ago is now much larger and there are two other developers who also work on the program with her. she would like a way to better manage the code so that she can revert to previous states if necessary and track changes made by each person. which technology would you suggest?

1. continuous integration application
2. code repository
3. workflow automation
4. chargebacks for each developer