Which of the following agents is used to disinfect?

One factor that determines skin color is the amount of oxygenated blood in the dermis of skin. The pigment in red blood cells that carry oxygen is called ________. 

Fill in the blank(s) with the appropriate word(s).

When peripheral vascular resistance is increased:

A. afterload increases and stroke volume decreases. B. blood return to the heart and cardiac output both increase. C. systolic blood pressure decreases and cardiac output increases. D. arterial blood pressure decreases and stroke volume increases.