Physicians Administer Drugs or Do Spinal Taps in the Lumbar

Physicians administer drugs or do spinal taps in the lumbar region of the spine. Which statement best describes why the lumbar region of the spine is used for such procedures?

A) It is because of gravity; the CFS has more pressure in the lumbar region of the spine.
B) This is where the dorsal and ventral roots are located and drugs administered to the roots are more effective.
C) It is due to the anatomical feature known as the cauda equina (Latin "horse tail") , meaning the spinal cord spreads out into individual nerves and the physician is less likely to harm the spinal cord.
D) Patients are less sensitive in this area of the back.
E) It is due to the anatomical feature of projection fibers that connect the spinal cord with the brain so the drugs will make it to the brain.