Question ID:PT53 S3 Q20 Passage:The ability of mammals to control their internal body temperatures is a factor in the development of their brains and intelligence. This can be seen from the following facts: the brain is a chemical machine, all chemical reactions are temperature dependent, and any organism that can control its body temperature can assure that these reactions occur at the proper temperatures. Stem:Which one of the following is an assumption on which the argument depends? Correct Answer Choice:DChoice A:Organisms unable to control their body temperatures do not have the capacity to generate internal body heat without relying on external factors. Choice B:Mammals are the only animals that have the ability to control their internal body temperatures. Choice C:The brain cannot support intelligence if the chemical reactions within it are subject to uncontrolled temperatures. Choice D:The development of intelligence in mammals is not independent of the chemical reactions in their brains taking place at the proper temperatures. Choice E:Organisms incapable of controlling their internal body temperatures are subject to unpredictable chemical processes.