A total of 9 units of a resource type are available, and given the safe state shown below, which of the following sequence will be a safe state?

A

$$<P4, P4, P3, P2>$$

B

$$<P4, P2, P1, P3>$$

C

$$<P4, P2, P3, P1>$$

D

$$<P3, P1, P2, P4>$$