The heritable variation among members of a population comes about because of environment.
The right answer is B. back pain from the compressed nerves
Narrow cervical canal symptoms can range widely from no symptoms to gait and balance disorders to radiculaglia when there is foraminal narrowing associated with central narrowing. Discrete balance disorders may be early signs of myelopathy (posterior cords). Later, the patients suffer from proximal weakness and paresthesia of the four limbs, as well as disorders of the fine motor skills of the hands (do not manage to close buttons of shirt, difficulties with the writing, etc., on reaching the lower motor neuron). In more advanced stages, gait disturbances and even later sphincter control disorders may occur (upper motor neuron involvement).
<span>A(n)PRIMITIVE CHARACTER is one present in the common ancestor and all members of the group
Primitive character is also known as ancestral character in phylogenetics. It is defined as a characteristic that has undergone little change since time immemorial and is inherited from a common ancestor of a clad.
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