I believe its D I hope it helps
A red blood cell's function is to transport oxygen.
Answer:
If they follow Mrs.Gren
Explanation :Mrs.Gren which stands for Movement, Respiration, Sensitivity, Growth, Reproduction, Excretion and Nutrition. If it doesn't have these characteristics then its non- living.
I'd say probably Biomass, not 100% sure but it's renewable, but it can create power and heat.