Answer:
DVD Drive, Headphones
Step-by-step explanation:
You need a CPU for sure, it is the main component known as the Central Processing Unit, and it provides instructios for the computer. A monitor is needed to visually see the internet, without a monitor, you would just be looking at your PC.
Headphones are not necessary because they are for personal audio, and most of the time, the internet is not audio.
A DVD drive is used to play DVD disks, which contains videos, movies, games, etc. The internet is not on a DVD.]
-Chetan K