GMAT Critical Reasoning
Not all life depends on energy from sunlight. Microbial life has been found in bedrock more than five kilometers below the surface of the Earth, and bacteria have been found on the deep ocean floor feeding on hydrogen and other gases rising from the interior of the Earth through vents in the ocean floor.
The statements above, if true, best support which of the following as a conclusion?
- A The location in the bedrock where microbial life was found was not near a system of volcanic vents through which hydrogen and other gases rose from the interior of the Earth.
- B Bacteria are able to exist at the molten center of the Earth.
- C A thorough survey of a planet's surface is insufficient to establish beyond a doubt that the planet contains no life.
- D Life probably exists on Sun-orbiting comets, which are cold agglomerations of space dust and frozen gases.
- E Finding bacterial remains in coal and oil would establish that the bacteria had been feeding on substances that had not been produced from the energy of sunlight.
Correct Answer: C