Which of the following is not a valid deadlock prevention scheme?

1.	Which of the following is not a valid deadlock prevention scheme?
A.	Release all resources before requesting a new resource
B.	Number the resources uniquely and never request a lower numbered resource than the last one requested
C.	Never request a resource after releasing any resource
D.	Request and all required resources be allocated before execution
Answer» D. Request and all required resources be allocated before execution

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Which of the following is not a valid deadlock prevention scheme?

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