**Core Concept:** Ribs are the bony elements that form part of the rib cage, which protects vital organs like the heart and lungs. There are typically 12 pairs of ribs in humans, numbered from 1 to 12, with the first and twelfth ribs being considered false ribs due to their unique developmental and functional characteristics.

**Why the Correct Answer is Right:** A false rib is a lateral costal cartilage which does not articulate with the vertebral column but with a costal cartilage of the adjacent true rib. This is why it is incorrect to call a false rib a true rib. The correct term for a false rib is "costal cartilage."

**Why Each Wrong Option is Incorrect:**
A. False rib (costal cartilage) is a misnomer as it does not articulate with a vertebra, but with a true rib.
B. True ribs (numbers 1-11) are the bony elements that articulate with the vertebral column and provide structural support to the thoracic cage.
C. This option is also incorrect as false ribs are costal cartilages, not bones.
D. Costal cartilages, which connect the ribs to the sternum, are not ribs and are not considered true ribs.

**Clinical Pearl:** Understanding the differentiation between true and false ribs is crucial for proper anatomical terminology and understanding rib cage structure and function. False ribs are costal cartilages that connect to adjacent true ribs, whereas true ribs articulate with the vertebral column.

**Correct Answer:** **Correct Answer: D. Costal cartilage**

**Explanation:** False ribs or costal cartilages are not bones but rather flexible structures that connect the ribs to the sternum. They do not articulate with the vertebral column, which is characteristic of true ribs. This misconception might lead to confusion in understanding the structure and function of the rib cage.