The opening at the base of the skull for the spinal cord is called

Haversian canals are found in .............

Which of the following statements are correct with reference to the human endoskeleton?
$A$. Human skull is monocondylic.
$B$. The joint between any two adjoining vertebrae is a cartilaginous joint.
$C$. In human beings, the number of cervical vertebrae is seven.
$D$. All ribs except the last $2$ pairs are bicephalic.
$E$. The occipital bone of the skull is articulated with the atlas vertebra.
Choose the correct answer from the options given below:

Which of the following bones is related to the skull?

Which of the following is a bone of the skull?

Where is the coccyx located?