Internal storage of the different versions of an artifact

  In version control, there has been some debate on how to implement the internal storage of the different versions of an artifact. One argument is to keep the complete copy of each version. Another is to keep only the delta changes from version to version, with the first version being the only complete copy. a. Give one reason why you may want to keep a complete copy of each version. b. Give one reason why you may want to keep only the delta. c. What would be the drawback of each of these approaches?