Consider a simple checkpointing protocol and the following set of oper

1.	Consider a simple checkpointing protocol and the following set of operations in the log.
A.	Undo: T3, T1; Redo: T2
B.	Undo: T3, T1; Redo: T2, T4
C.	Undo: none; Redo; T2, T4, T3, T1
D.	Undo: T3, T1, T4; Redo: T2
Answer» B. Undo: T3, T1; Redo: T2, T4

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Consider a simple checkpointing protocol and the following set of operations in the log.

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