The following table explains the rules of 3 variants of the CSMA protocol. CSMA Protocol Sender's listening-and-transmission rules Nonpersistent If medium is idle, transmit. If medium is busy, wait random amount of time and sense channel again. 1-persistent If medium is idle, transmit (i.e., transmit with probability 1). If medium is busy, continue sensing until channel is idle; then transmit immediately (i.e., transmit with probability 1). P-persistent If medium is idle, transmit with probability p. If medium is busy, continue sensing until channel is idle; then transmit with probability p. Suppose that Device A, Device B and Device C use CSMA protocol to access a shared medium. At time t=0, each device has a packet to transmit. What happens if Device A is 0.5-persistent and Device B and C are 1- persistent? a. All packets collide O b. Packet A and C collide, and possibly B with probability of 1/2 O c. Packet B and C collide, and possibly A with probability of 1/2 O d. Packet A and B collide, and possibly C with probability of 1/4 Packet A and C collide, and possibly B with probability of 1/4