Irregular bones include which of the following?

• A. Vertebrae and facial bones
• B. Carpals and tarsals
• C. Ribs
• D. Clavicles

Answer: (A)

Irregular bones are those with complex shapes that don’t fit the standard long, short, or flat bone categories. Vertebrae and many facial bones are classic irregular bones because their surfaces and processes have multiple articulations and specific roles—protecting the spinal cord and shaping the face, respectively. The other options align with other bone groups: carpals and tarsals are short bones, ribs are flat bones, and the clavicle is typically treated as a long bone due to its elongated form. So vertebrae and facial bones best fit the irregular bone category.