Which statement is valid?

A.
Multiple PTCPIP subsystems and multiple conventional TCPIP subsystems can be on one
system.

B.
Multiple PTCPIP subsystems and only one conventional TCPIP subsystem can be on one
system.

C.
Only one PTCPIP subsystem and multiple conventional TCPIP subsystems can be on one
system.

D.
PTCPIP subsystems and conventional TCPIP subsystems cannot be used on the same
system.