Which of the following best describes a centric holding cusp of a mandibular left second molar?
a. it is the distofacial cusp and occludes in the embrasure between maxillary first and second molars.
b. it is the distofacial cusp and occludes in the central fossa of a maxillary second molar.
c. it is the distolingual cusp and occludes in the embrasure between maxillary first and second molars.
d. it is the distolingual cusp and occludes in the central fossa of a maxillary second molar.

The answer is B- It is the distofacial cusp and occludes in the central fossa of a maxillary second molar.

Explanation:

Centric holding cusp are also called Stamp Cusps, it is a type of cusp in which include the facial cusp of the mandibular and palatal cusps of the maxillar posterior teeth. The occlude into the central fossa and marginal ridges of the opposing teeth. Centric occlusion is the position of mandibular condyle when the jaws are closed and the teeth are in maximum intercuspation. Occlusion is the static relationship of teeth, it means "closing up".

clumped distribution, because you'de have all of the population gathered in a relatively small are.

it's the most common because it provides protection and a mate for reproduction

example: humans, seeweed, cattles, etc.

most community's take hundreds of years to become stable