How can you tell by simple observation whether bleeding is arterial or venous?

Most people believe that internal bleeding is bleeding that can not be seen outside the body and blood accumulates inside the body. Internal bleeding can occur in tissues, organs or other cavities of the body including the head, chest and abdomen (eye tissue covering the heart, muscles, joints, etc.).

External bleeding is fairly easy to recognize and detect. If the skin is injured or wounded as a result of sprains, a puncture or abrasion, bleeding occurs. It could take even few hours and worsen when significant amounts of blood are involved or in cases that form a clot large enough to compress the body and to prevent its functioning properly.
Internal bleeding occurs when the damaged artery or vein allows blood leak from the bloodstream and it collects inside the body. The amount of bleeding depends on the degree of deterioration of the body and the blood vessels that provide its irrigation, and the body's ability to repair existing lesions in blood vessels. The recovery process involves the process of blood clotting and the mechanism by which blood vessels constrict and reduce blood flow to the injured area.

It would be answer choice b (1975)