Why can it be incorrect to treat a modem and a router as the same device?

Correct answer: A modem converts service signals while a router routes data between networks

A modem and a router have different governing functions even though many household units combine them. A modem converts signals between the internet service line and digital network data, while a router directs packets between the local network and other networks. Thus option D is correct. The other choices wrongly describe both devices as internal, printing, or storage equipment and ignore their communication roles.