The primary ossification center of a long bone is located:
A. at the midpoint of the diaphysis
B. in the epiphysis
C. in the medullary cavity
D. at the epiphyseal cartilage

That would be A.

A. At the midpoint of the diaphysis.

the glands which are associated with each description is given below:

pancreas - is an endocrine and exocrine gland that secretes juices with enzymes for digestion. salivary glands- with protection and digestion in the mouth. liver- secretes bile for digestion.   lachrymal glands - secrete tears to moisten eyes and protect them from particles and infection.   sweat gland -regulates water, salt, and temperature. oil glands - to form a protective barrier on the skin.   goblet cells - secrete mucus for protection.