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In humans, the pilomotor reflex leads to the response commonly known as goose bumps, and this response is widely considered to be vestigial—that is, something formerly having a greater physiological advantage than at present. It occurs when the tiny muscle at the base of a hair follicle contracts, pulling the hair upright. In animals with feathers, fur, or quills, this creates a layer of insulating warm air or a reason for predators to think twice before attacking. But human hair is too puny to serve these functions. Goose bumps in humans may, however, have acquired a new role. Like flushing—another thermoregulatory (heat-regulating) mechanism—goose bumps have become linked with emotional responses, notably fear, rage, or the pleasure of, say, listening to beautiful music. They may thus serve as a signal to others.
In explaining the “new role” (line 7) that goose bumps in humans may have acquired, the author assumes which of the following?
A.Emotional responses in humans can be triggered by thermoregulatory mechanisms.
B.The perceptibility of emotional responses to other humans offers some kind of benefit.
C.If human hair were more substantial, goose bumps would not have acquired a new role.
D.Goose bumps in animals with feathers, fur, or quills may also be linked to emotional responses.
E.In humans, goose bumps represent an older physiological response than flushing.
Which of the following best describes the primary function of the next-to-last sentence (“Like . . . music”)?
A.It makes a distinction between two types of mechanisms.
B.It corrects a common misconception about the role of goose bumps in humans.
C.It suggests reasons for the connection between emotional responses and goose bumps in humans.
D.It suggests that flushing and goose bumps signal the same emotional state.
E.It helps explain a possible role played by goose bumps in humans.
