Fontanelle refers to soft spots on a baby's head that allow the skull to pass through the birth canal by enabling what?

• A. Bones to fuse
• B. Bones to rotate
• C. Bones to compress
• D. Bones to flex

Answer: (D)

Fontanelles are gaps between the infant skull bones where sutures have not yet fused, giving the skull temporary flexibility. This flexibility lets the bones move and overlap slightly as the head passes through the birth canal, a process known as molding. By allowing the skull to bend rather than staying rigid, the head can adapt to the shape and size of the birth canal. So the soft spots enable the bones to flex, which is why the best choice is that they allow the head to flex.