Number of floating ribs in human body is:

Find out the correct option regarding true sentence/s from the followings- 

(i) Human skull is dicondylic like reptiles.

(ii) Foramen of Magnum is found at the anterior side of skull

(iii) Atlas vertebrae helps in rotation of neck.

(iv) Spinal cord passes to the brain through Foramen of Magnum.

The protein present in the bones is known as

The pectoral and pelvic girdles and the bones of limb form