Which term refers to the first and second cervical vertebrae?

• A. C-spine
• B. Atlas-axis complex
• C. C1, C2
• D. First cervical vertebra

Answer: (C)

The first two cervical vertebrae are named for two distinct bones: the atlas (C1) and the axis (C2). Saying them together as C1, C2 directly identifies the pair of vertebrae involved, which is exactly what the question asks for. The atlas-axis complex is a real term that describes how these two bones interact at the joint, but it’s a descriptive label of their relationship rather than a precise naming of the two vertebrae themselves. Other options are less precise: the C-spine refers to the entire cervical region, not just the first two vertebrae; the first cervical vertebra only names one bone (C1); and the atlas-axis complex, while accurate, doesn’t explicitly name both vertebrae.