Compared with SoBig. F, Blaster was a virus that was______.

A．is a valuable source of social information
B．produces a joy that most people in society need
C．brings people the feel of being part of a group
D．satisfies people's need of being unusual

A．is a wicked worm causing as many damages as Blaster did
B．is a program designed by Haley to detect worms like Blaster
C．is a program intended to fix the infected machines
D．is a worm meant to defeat the virus with "pings"