launch/9976929 A _ attack allows hackers to shut down or block access to websites and other network resources by overwhelming them with requests. O DDOS O phishing O pretexting O scareware 2. A _ is a fully-contained program that self-replicates and spreads through computers and networks. O virus zombie O worm O Trojan horse 3. A is a program that disguises itself as an interesting, useful, or desirable program in order to gain access to your system. virus O zombie O worm O Trojan horse 4. A _ is an inexpensive product that guards connected equipment against large power spikes or surges that may infrequently occur. O surge protector O RAID O switch O gateway