Sentences of a paragraph are given below in jumbled order. Arrange the sentences in the correct order to form a meaningful and coherent paragraph.

A. This washes the eye with the salty secretion from the tear or lachrymal glands.

B. These glands are situated behind the upper eyelid at the outer corner of the eye.

C. It is wonderful that human eyes blink an average of once every six seconds.

D. Each tear gland is about the size and shape of an almond.