Question

What is it called when a molecule uses energy to move across a semipermeable membrane?

Answer 1

When molecules uses energy for transportation across the cell, then it is known as "Active Transport"

So, option B is your answer.

Hope this helps!

Answer 2

Answer: Active Transport

Explanation:

The movement of the particles across membrane needs energy. Energy is required in the condition where there is a movement of particles from a lower concentration to higher concentration.

It requires cellular energy for the movement of the particles. The larger molecules needs energy to move across concentration gradient.