A Buffer Overflow attack involves:

A.
Using a trojan program to direct data traffic to the target host’s memory stack

B.
Flooding the target network buffers with data traffic to reduce the bandwidth available to legitimate users

C.
Using a dictionary to crack password buffers by guessing user names and passwords

D.
Poorly written software that allows an attacker to execute arbitrary code on a target system

Explanation:
B is a denial of service. By flooding the data buffer in an application with trash you could get access to write in the code segment in the application and that way insert your own code.