Misalignment of the spine leading to lower-back pain can be caused by

Causation can be proved by using an

Astructural difference between the trachea and esophagus that prevents the trachea from collapsing is the presence of: a) smooth muscle b) skeletal muscle c) respiratory cilia d) rings of cartilage

Which of the following must be treated under the care of a physician and is mainly considered a medical condition? a. scoliosis b. lordosis c. kyphosis d. all of the above