This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Anatomy
Ribs are developed from ? 
Select and explain. 
A. Cloaca, B. Sclerotome, C. Endodermal cloaca, D. Primitive gut
B: Sclerotome
Answer: B: Sclerotome 
Explanation: Ribs are derived from lateral cells of sclerotome.Derivatives of paraxial mesoderm Paraaxial mesoderm is organized into somites which in turn gives rise toi) Sclerotomes : Form axial skeleton including veebrae, ribs and pas of neurocranium.ii) Myotomes : Form all voluntary (skeletal) muscles of head, trunk and limbs.iii) Dermatomes : Form dermis of skin, especially over dorsal regions.