Which sentence best describes active transport?

1) A substance moves into or out of a cell using energy.

2) A substance moves from an area of high concentration to an area of low concentration.

3) Water moves into and out of the cell.

4) A material moves into or out of a cell without using energy.

Answer: Option A

Explanation:

The active transport can be defined as the transport which is uses energy to transport materials.

The materials from the inside of the cell is transported to the outside of the cell or the materials from the outside of the cell is transported to the inside of the cell.

There is a need of energy because the substance needs to move against the concentration gradient.

1) a substance moves into and out of the cell using energy (in the form of ATP)