Answer:
b
Explanation:
a semi permeable membrane requires no energy since it allows safe passage of molecules from low to high think of it like a tea bag it has a high concentration and the low concentration is the hot water.
I hope it helps
I was thinking maybe it's a heart sinus rhythm but it doesn't have the right characters it should have it looks like a blood pressure with a sinus arrhythmia but it's not
C. it cant be a since it exist