The molecules in this diagram are moving in a

A) random motion from one part of a membrane to another, from a higher concentration to a lower concentration.

B) random motion from one part of a membrane to another, from a lower concentration to a higher concentration.

C) straight line motion from one part of a membrane to another, from a higher concentration to a lower concentration.

D) straight line motion from one part of a membrane to another, from a lower concentration to a higher concentration.

Answer:
A) random motion from one part of a membrane to another, from a higher concentration to a lower concentration.