DiGeorge Syndrome and Other Developmental Anomalies

The correct answer is E.

Explanation:

The third pharyngeal pouch normally gives rise to the inferior parathyroid glands and the thymus. Cells from these pouches migrate caudally in the embryo to the eventual location of these organs. The superior parathyroid glands are derived from the fourth pharyngeal pouch. The absence of these organs is found in DiGeorge syndrome, which typically presents with immunodeficiency and hypoparathyroidism.

The second pharyngeal arch (choice A) gives rise to several skeletal and muscular structures. These include the stapes, styloid process, stylohyoid ligament, a portion of the hyoid bone, the stapedius muscle, stylohyoid muscle, posterior digastric muscle, and all of the muscles of facial expression.

The second pharyngeal cleft (choice B) is normally obliterated. A persistence of this cleft may result in a lateral cervical cyst, sinus, or fistula.

The second pharyngeal pouch (choice C) gives rise to the tonsillar fossa and the palatine tonsils.

The third pharyngeal arch (choice D) gives rise to most of the hyoid bone and the stylopharyngeus muscle. The third aortic arch, which passes through the third pharyngeal arch, gives rise to the common carotid artery and the internal carotid artery.

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