When the concentration of molecules on both sides of a membrane is the same, the molecules will A move across the membrane to the inside of the cell
B stop moving across the membrane
C move across the membrane is both directions
D move across the membrane to the outside of the cell

B. Stop moving across the membrane.

Explanation:

Movement of molecules across the cell membrane depends on the concentration of the molecules on both sides of the membrane i.e the higher the concentration of molecules,the higher the attraction,since the molecules have the same concentration on both sides of the membrane the molecules does not move to either of the sides.

kelp are large brown algae that live in cool, relatively shallow waters close to the shore. they grow in dense groupings much like a forest on land. these underwater towers of kelp provide food and shelter for thousands of fish, invertebrates, and marine mammal species.

e) all of the above