Answer :
Final answer:
The correct option is c) 15-25. The annulus fibrosus is comprised of 15-25 concentric layers, serving as the protective outer part of each intervertebral disc.
Explanation:
The correct option is c) 15-25. The annulus fibrosus is the tough, fibrous outer layer of an intervertebral disc, consisting of 15-25 concentric layers. It's designed to form a sturdy circle and is attached to the margins of the vertebral bodies. The role of the annulus fibrosus is critical as it contains and protects the nucleus pulposus, the inner gel-like core that maintains disc height and flexibility, crucial for weight bearing and motion.