Could I have some help on this plz?

Jared and Marie went to Supply Depot to purchase a door that would articulate in two directions and allow them to pass more easily between the kitchen and dining room. Marie had seen one on television and thought the free-swinging door would be easier to use.

Based on its context in the paragraph above, what is the meaning of the word articulate?
A.
to bend or hinge
B.
to allow double entry
C.
to be brightly colored
D.
to be effective

Thanks.