单选题 The author's primary purpose in the passage is to

• (A) describe the limits of biologists' understanding of the phenomenon of cellular dormancy
• (B) explain how certain organisms have adapted to withstand environmental adversity
• (C) contrast the survival techniques of two organisms which use dormancy to survive hostile environments
• (D) explain why endospores are so adept at surviving the traditional canning process
• (E) suggest which methods are effective for killing endospores at which are not