This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Nervous System, Subject name: Physiology
Compared to an unacclimatized person, one who is acclimatized to cold has: 
Select and explain. 
A. Higher metabolic rate in the cold, to produce more heat, B. Lower metabolic rate in the cold, to conserve metabolic energy, C. Lower peripheral blood flow in the cold, to retain heat, D. Various combinations of the above, depending on the environment that produced acclimatization.
D: Various combinations of the above, depending on the environment that produced acclimatization.
Answer: D: Various combinations of the above, depending on the environment that produced acclimatization. 
Explanation: Ans. D. Various combinations of the above, depending on the environment that produced acclimatization. Acclimatization to cold produces several different (and contrasting) sets of changes, depending on the acclimatizing environment (and, perhaps, on characteristics of the population being acclimatized).