Well he used both. But true is the answer
Overproduction of offspring, inherited variation, and the struggle to survive.
So: b, d, and e
Spinal nerves<span> or motor axons </span>exit<span> the </span>vertebral column<span> via the ventral root where they synapse on motor neuro ganglia, then the ventral horn. sensory </span>nerves<span> enter the</span>spinal<span> cord via dorsal horn, synapse on dorsal ganglia, and enter the </span>spinal<span> cord. ... a painful rupture of fibrocartilage of discs between </span>spinal vertebrae<span>.
hope my answer helps!</span>