Which of the following is NOT a characteristic of active transport? * A)It moves substances against a concentration gradient
B)It requires energy from the cell
C)It involves facilitated diffusion
D)It may use carrier proteins that often function as the sodium potassium pump

It involves facilitated diffusion.

Explanation:

Facilitated diffusion uses channel proteins. Channel proteins allow substances to travel through a membrane going with the gradient. Since active transport goes against the gradient, facilitated diffusion would not be a characteristic of it.

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