Which of the following best describes a Smurf attack?
a. It sends ping requests to a subnet, requesting that devices on that subnet send ping replies to a target system.
b. It sends ping requests in segments of an invalid size.
c. It intercepts the third step in a TCP three-way handshake to hijack a session.
d. It uses Trojan horse applications to create a distributed collection of “zombie” computers, which can be used to launch a coordinated DDoS attack.