The tubercle found on the neck of a rib articulates with a facet found on the

The tubercle found on the neck of a rib articulates with a facet found on the TRANSVERSE PROCESS OF A THORACIC VERTEBRA. 
The tubercle refers to a small, rounded projection found on the surface of bones while a facet refers to the small, smooth area on a bone.
What this statement is saying is that, the tubercle that is located at one end of the rib formed a joint with the thoracic vertebra.

C) reflection (i also looked up the other choices just to make sure)