Which of the sentences below best expresses the essential information in the highlighted sentence in the passage? Incorrect choices change the meaning in important ways or leave out essential information. A. Thus, although amphibians use the various mechanisms described above, they have hardly any control of their body temperature. B. Thus, by the mechanisms described above, amphibians are quite capable of controlling their body temperature to survive extreme ambient temperatures. C. Thus, unless they can use the mechanisms described above, amphibians are at the mercy of ambient temperatures. D. Thus, the mechanisms described above give amphibians control over much more than just their body temperature.