which level the somites initially form ?

Ans. is 'b' i.e., Cervical levelThe first pair of somites develop a sho distance posterior to the cranial end of the notochord, and the rest of the somites from caudally."By the 20" day, the first pair of somites have formed in neck region." Textbook of embryologyParaxial mesoderm differentiates into somites. By the end of 20th day, the first pair of somites have formed in neck region. After this, about 3 pairs of somites are formed per day and by the end of 5" week about 42-44 somite pairs are formed (4-occipital, 8-cervical, 12-thoracic, 5-lumbar, 5-sacral and 8-10 cooccygeal). Somites are fuher differentiated into :-Dermatomyotome :- Give rise to skeletal muscles and dermis.Sclerotomes :- Give rise to veebral column.