Harold is performing a penetration test and would like to force a switch to fall back to forwarding mode. Which of the following attacks would be most helpful to Harold in meeting his goal? a) ARP spoofing
b) MAC flooding
c) Active sniffing
d) Passive sniffing

a) ARP spoofing

Explanation:

ARP Spoofing is a term in a computer networking, which is can be used as a penetration technique or attack methods in which an attacker sends (spoofed) Address Resolution Protocol (ARP) messages onto a local area network. The purpose is to spoof the MAC address of a trusted host and forge ARP request to overload the Switch. This will set the Switch in “FORWARD MODE” which will leads to any traffic meant for that MAC address to be sent to the attacker instead.

i think it's b or c hope this

d. i assume the underlined word is "role." reformat if it isn't.

explanation:

role is closest to part because when replacing words, "playing a vital decision," "playing a vital activity," and "playing a vital dollar" don't make logical sense. the only meaningful choice is "playing a vital part."

this fits one of merriam-webster's definitions of role: "a function or part performed especially in a particular operation or process."