Question

which of the following constitutes the pectoral girdle?
a clavicles only
b clavicles, scapulae, humerus, radius, and ulna
c clavicles, scapulae, and humerus
d clavicles and scapulae
e clavicle, scapula, humerus, radius, ulna, and carpal bones

Explanation:

The pectoral girdle is a set of bones that connects the upper limb to the axial skeleton. It consists of two bones: the clavicle (collarbone) and the scapula (shoulder blade).

• Option A: Only clavicles are not enough as scapulae are also part of the pectoral girdle.
• Option B: Humerus (upper arm bone), radius and ulna (forearm bones) are part of the upper limb, not the pectoral girdle.
• Option C: Humerus is part of the upper limb, not the pectoral girdle.
• Option D: Clavicles and scapulae are the correct components of the pectoral girdle.
• Option E: Humerus, radius, ulna and carpal bones are part of the upper limb, not the pectoral girdle.

Answer:

D. clavicles and scapulae