Which of the following statements about the vertebral column is/are true? The vertebral column consists of 33 vertebral bone segments divided into ...

Which of the following statements about the vertebral column is/are true?
The vertebral column consists of 33 vertebral bone segments divided into five regions: cervical, thoracic, lumbar, sacral, and coccygeal.
The cervical and lumbar regions have an anterior convex curvature called lordosis, while the thoracic and sacrococcygeal regions have an anterior concave curvature called kyphosis.
The kyphotic curvature in the thoracic and sacrococcygeal regions provides space to accommodate organs within the thoracic and pelvic cavities, due to its anterior concave curvature, allowing for proper adjustment of internal organs.
Flexion of the vertebral column flattens the cervical and lumbar lordosis, but accentuates the thoracic kyphosis.
Further extension of the vertebral column accentuates the cervical and lumbar lordosis, but reduces the thoracic kyphosis.
In the cervical region, extensor muscles pull the head and neck when the infant begins to observe the surroundings, contributing to the development of cervical lordosis.
More caudally, developing hip flexor muscles pull inferiorly on the front of the pelvis as the child begins to walk, resulting in the formation of lordosis in the lumbar spine.
The natural lordosis of the lumbar spine is a biomechanically favorable adaptation in humans, as it minimizes the local muscular effort required to maintain an upright posture.
The cervicothoracic and thoracolumbar regions are especially prone to premature loosening of spinal fusion surgeries due to shear forces.
In certain pathological conditions, such as anterior spondylolisthesis, the lower lumbar vertebrae can excessively slide relative to the sacrum, which is considered a potentially serious condition.