The answer to this is C. In order to make the transition from legacy CRM to Salesforce, there should be a one-time data migration that should occur. This means that there is a need to enable the set audit fields. The permission should be given to the user who is in charge of loading the data during the whole time that migration is taking place.
If this would not be done, there may be some issues that will occur during the migration process. This is something that needs to be avoided so that important company data will not get lost while the change is taking place.