A contactor:

A) is another name for a relay.
B) is designed to handle heavy power loads.
C) always has an overload relay physically and electrically attached.
D) is a physically small relay.

A contactor is designed to handle heavy power loads, while a relay is typically used for smaller loads. Contactors are commonly used in industrial settings for controlling motors and other high-power devices, and they often have multiple sets of contacts to allow for more complex control schemes. While some contactors may have overload protection built in, this is not universal and should not be relied upon without verifying the specific device's specifications.