Which of the following types of attacks does DHCP snooping prevent？（Choose all that apply.）（）

A.Attacker sends multiple DHCP requests flooding DHCP server
B.Attacker connects rogue server initiating DHCP requests
C.Attacker connects rogue server replying to DHCP requests
D.Attacker sends DHCP jam signal causing DHCP server to crash
E.Attacker sends gratuitous ARP replies， thereby jamming the DHCP server
F.Attacker sends unsolicited DHCP replies， thereby jamming the DHCP server