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
Transition temperature of lipid bilayers of cell membrane is increased by- 
Select and explain. 
A. Cholesterol, B. Saturated fatty acids, C. Hydrocarbons, D. Unsaturated fatty acids
B: Saturated fatty acids
Answer: B: Saturated fatty acids 
Explanation: B i.e Saturated fatty acids