Final answer:
Rodney should use a CD writer to write, erase, and overwrite files on a CD. A CD writer is also known as a CD burner and is different from a CD-ROM drive, which can only read data, or a CD player, which is meant for music.
Step-by-step explanation:
If Rodney wants to be able to write, erase, and overwrite the files on a CD, he should get a CD writer. A CD writer, often called a CD burner, is a peripheral device that allows you to create (write), erase, and rewrite (overwrite) data on a rewriteable CD (CD-RW).
Unlike a CD-ROM drive, which can only read data from CDs, or a standard CD player, which is meant for music playback, a CD writer is designed with the ability to modify data on a CD. Therefore, the correct answer is 4) CD writer.