Which of the following is a correct difference between active transport and facilitated diffusion?

• A. Active transport involves transport proteins, and facilitated diffusion does not.
• B. Facilitated diffusion can move solutes against a concentration gradient, and active transport cannot.
• C. Facilitated diffusion requires carrier proteins, but active transport requires channel proteins.
• D. Facilitated diffusion involves transport proteins, and active transport does not.
• E. Active transport requires an input of energy, and facilitated diffusion does not.