B

The condylar and temporal blastemas appear at 7–8 weeks, and cavitation with formation of the inferior joint space occurs in the 9–10 week period; by the 10th week a recognizable temporomandibular joint is present in the embryo [Mérida-Velasco, 1999, PMID 10321990; Carini, 2008, PMID 18333411].