D

Reasoning: Synarthroses are the immobile fibrous joints. Texts describe (1) cranial sutures as “synarthroses connecting the bones of the head” [Savoldi 2018, PMID 28610544]; (2) gomphosis (dento-alveolar joint) as a type of synarthrosis [Nägerl 1991, PMID 2064014]; and (3) syndesmosis, e.g., the distal tibiofibular syndesmosis, as a fibrous joint linking two bones with ligaments, i.e., a synarthrosis variant [Hermans 2010, PMID 21108526]. Thus all three listed joints are examples of synarthroses.