A magnet can hold a piece of paper to the door of a refrigerator. How does the magnet stick without touching the door?

A.
Gravity attracts the magnet to the door.

B.
Atoms from the magnet pass through the paper and touch the door.

C.
The magnet induces a magnetic field in the paper.

D.
The magnetic force of the magnet can act at a distance.

D. The magnetic force of the magnet can act at a distance.