Several hypotheses have been formulated to explain the origin of life, and the most accepted is that of the gradual evolution of chemical systems. ...

Several hypotheses have been formulated to explain the origin of life, and the most accepted is that of the gradual evolution of chemical systems. Accepting this hypothesis, and the supposed conditions of the primitive atmosphere of the Earth, formed of methane (CH4), ammonia (NH3), hydrogen (H2), and water vapors (H2O), choose the correct alternative:


a) The first living beings were aerobic heterotrophs because, with the fermentation of organic molecules, they were able to obtain energy and also release enough oxygen to carry out respiration.
b) The first living beings were autotrophic photosynthesizers, since they were able to break down water molecules existing in atmospheric vapors and use methane as a source of carbon.
c) The first living beings were anaerobic heterotrophs because the primitive atmosphere did not have oxygen and carbon dioxide, essential for aerobic respiration and photosynthesis.
d) The first living beings were formed by the coacervation of organic molecules found in meteorites that fell on the primitive Earth.