Question

Unique feature of osmosis is that

(1) energy is required
(2) it involves movement of solutes
(3) it occurs across membranes only
(4) it is seen only in animals

Answer 1

I believe the answer is (3)

Step-by-step explanation:

"Osmosis is a special type of diffusion, namely the diffusion of water across a semipermeable membrane"

"Osmosis only occurs with a semipermeable membrane"

Khan and sciencedirect