Which arch is associated with the stylopharyngeus muscle and the greater horn of the hyoid bone?

• A. First arch
• B. Second arch
• C. Third arch
• D. Fourth arch

Answer: (C)

The key idea is how the pharyngeal arches map to muscles and skeletal parts. The stylopharyngeus muscle is a muscle that comes from the third pharyngeal arch, and its nerve supply is the glossopharyngeal nerve (CN IX), which is characteristic of the third arch. At the same time, the hyoid bone parts are formed from the arches as well: the greater horn and the lower part of the hyoid come from cartilage of the third arch, while the second arch contributes the lesser horn and upper body. So both the stylopharyngeus muscle and the greater horn of the hyoid bone originate from the third arch, making it the correct association.