This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Head and neck, Subject name: Anatomy
Joint involved in movement of head from left to right is 
Select and explain. 
A. Atlanto occipital, B. Atlanto axial, C. C2- C3 Joint, D. C3- C4 Joint
B: Atlanto axial
Answer: B: Atlanto axial 
Explanation: * Atlanto-occipital (between skull and C1) joint permit nodding of head ( as when indicating approval or YES) and Atlanto-axial joint permits the head to be turned from side to side (as indicating disapproval or NO). * Atlantoaxial is a combination of three synol joints. The aiculation is at three places - a pair of lateral masses and a median complex (between dens of axis and anterior arch & transverse atlantal ligament) * Rotation movement takes place simultaneously at all joints and the normal range of rotation is 40 degrees. * The muscles which produce these movements are obliquus capitis inferior, rectus capitis posterior major, ipsilateral splenius capitis and contralateral sternocleidomastoid. Ref:- Gray's Anatomy 41st Edition; Pg num:- 737