What mechanism can be used to ensure that a failed transaction or system failure returns the subject to a meaningful point in some process?

A.
Bookmark

B.
Cyclical redundancy check

C.
Inference

D.
Checkpoint

Explanation:
Checkpoints create a fallback strategy for an application that returns the user to a point prior to the failure of some process. Savepoints and checkpoints are similar in nature. A savepoint is used to periodically save the state of the application and the user’s information, whereas a checkpoint saves data held in memory to a temporary file. Both are used so that if the application endures aglitch, it has the necessary tools to bring the user back to his working environment without losing any data. You experience this with a word processor when it asks youif you want to review the recovered version of a file you were working on.