This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Physiology
[{'content': 'Transpo of neutral substances across the cell membrane occurs \nSelect and explain. \nA. Porins, B. Lonophore, C. Lipopolysaccharides, D. Diffusion', 'role': 'user'}, {'content': 'Answer: D \nExplanation: D i.e. DiffusionTranspo simple passive diffusion is oured by small size, lipid solubility (hydrophobicity) absence of charge (neutrality), and absence of polarity (nonpolar nature)Q.', 'role': 'assistant'}]