The following statements concerning the head and neck, which are CORRECT?
A.
The mastoid process of the temporal bone cannot be palpated in the newborn
B.
The deep cervical lymph nodes are situated in the neck along a line that extends from the midpoint between the tip of the mastoid process and the angle of the mandible down to the sternoclavicular joint
C.
The external jugular vein runs down the neck from the angle of the jaw to the middle of the clavicle
D.
The roots of the brachial plexus emerge into the posterior triangle on the neck between the scalenus anterior and scalenus medius muscles