Answer:
Option C, It is a barrier with tiny openings that let some, but not all, materials pass through
Step-by-step explanation:
A semipermeable membrane is a biological membrane that allows some substances to pass through it. Such type of membranes are also referred as selectively permeable membrane as they do not allow all substances to pass through it non-distinctively.
For example the cell membrane , wall of arteries, wall of intestine etc. are semipermeable membrane.
Hence, option C is correct.