What does the letter D stand for in reference to the chain-of-survival concept in cardiopulmonary resuscitation?

The person who is ultimately responsible for payment to the medical office is called the:

guarantor. patient. guardian. insured.

The exchange of oxygen and carbon dioxide between the blood and the cells of the body is called:

A) internal respiration. B) external ventilation. C) external respiration. D) internal ventilation.