Question: A fever is a response to a disease-causing agent infecting the body. Raising one's body temperature changes the shape of enzymes in the agent so it cannot reproduce. Which statement best describes a fever?

  Options: 
 A. A fever is an internal response to an external stimulus.
 B. A fever is an internal response to an internal stimulus.
 C. A fever is an external response to an external stimulus.
 D. A fever is an external response to an internal stimulus.
Answer: B