The Figure Below Illustrates How Food Is Transported in Phloem

The figure below illustrates how food is transported in phloem tissue.
At what step(s) during the movement of sugar is metabolic energy provided by the plant?

A) Steps 2 and 4, when water enters and leaves phloem
B) Step 1, when high concentrations of sugar are created in the phloem
C) Step 3, when growing cells in buds pump in sugar from the phloem
D) All of the steps require the expenditure of metabolic energy.