Answer: Option D
:
D
The vertebræ are thirty-three in number, and are grouped under the namescervical, thoracic, lumbar, sacral,andcoccygeal,according to the regions they occupy; there are seven in the cervical region, twelve in the thoracic, five in the lumbar, five in the sacral, and four in the coccygeal.
The vertebræ in the upper three regions of the column remain distinct throughout life, and are known astrueormovablevertebræ; those of the sacral and coccygeal regions, on the other hand, are termedfalseorfixedvertebræ, because they are united with one another in the adult to form two bones—five forming the upper bone orsacrum,and four the terminal bone orcoccyx.