Which of the Following Statements Is True

Multiple Choice

Which of the following statements is true?

A) Oxygen moves into cells by diffusion, but carbon dioxide is moved by active transport.
B) Oxygen and carbon dioxide move into and out of cells and alveoli passively by diffusion.
C) Carbon dioxide and oxygen are actively transported into and out of blood by diffusion.
D) Oxygen moves into cells by diffusion, but in the alveoli it is actively transported.