Final answer:
The term for a tooth that moves when in function is 'Mobile tooth.' The masseter muscle action is for chewing, not tooth mobility. Gomphosis is the joint where the tooth is anchored into the jawbone and is not indicative of a tooth's mobility in function.
Step-by-step explanation:
To describe a tooth that moves when in function, the correct term is b. Mobile tooth. A mobile tooth exhibits movement under normal biting or chewing forces. In contrast, an ankylosed tooth would not move, as it is rigidly fused to the bone. A hypermobile tooth would imply an excessive degree of movement, possibly due to advanced periodontal disease, while a non-occluding tooth does not come into contact with its opposing counterpart during biting or chewing.
The action of the masseter muscle, as given in the provided question, is b. chewing. It's one of the main muscles responsible for elevating the mandible (lower jaw) to close the mouth and is crucial for the process of mastication (chewing).
Gomphosis refers to a joint where the tooth is anchored into its bony socket, such as in the maxillary bone or the mandible bone. This type of joint is stabilized by the periodontal ligament and is classified as a synarthrosis due to its immobility. It is not directly related to tooth mobility in function but refers to the normal anchoring of teeth.