1. B. To delete 15,000 inactive Accounts in a single transaction after a deployment: Anonymous Apex can be used to quickly run scripts that perform bulk operations, such as deleting a large number of records. This is particularly useful immediately after a deployment when certain clean-up or data correction tasks need to be performed.
2. C. To run a batch Apex class to update all Contacts: Anonymous Apex is often used to kick off batch processes. You can execute Anonymous Apex code to start a batch job that processes a large number of records, such as updating all Contact records according to some business logic.