Aprokaryote is most likely to use which of the following modes of metabolism to release energy if it is in an environment without oxygen, dies when exposed to oxygen, and uses fermentation? a. obligate anaerobe b heterotroph c. facultative anaerobe d. photoautotroph

It's letter A - Obligate anaerobe.

Obligate anaerobes are microorganisms killed by normal atmospheric concentrations of oxygen. A facultative anaerobe prefers to produce energy in the presence of oxygen but can survive without it. A photoautotroph is an organism that converts light energy into chemical energy. Prokaryotes may perform aerobic (oxygen-requiring) or anaerobic (non-oxygen-based) metabolism and some can switch between these modes. Since we're talking about an environment without oxygen and dies when exposed to oxygen, the preferable answer is A.

C14 dating since carbon is present in both living and no living objects .