Answer:
The answer is 'D'- only port replicators have expansion slots.
Explanation:
A port replicator is a kind of attachment which allows multiple devices to be attached to the laptop through a simple USB. The devices can be a monitor, printer, large monitor, keyboard etc.
On the other hand a docking station allows portable computers to be connected to other hardware devices and get converted into a desktop system. Docking station can be plugged Ā hot or cold. Cold docking is carried out when the system is shut down and hot docking occurs when the system is still running and the docking station is connected.