The answer is E.
Chemoautotrophs are organisms that use inorganic <span>compounds as an energy source and CO2 as a carbon source. The organisms live in </span>hostile environments like dark depths of the sea. Inorganic energy sources that they use are mostly hydrogen sulfide, elemental sulfur, ferrous iron, molecular hydrogen, and ammonia.
The answer is (b) for example lemon juice is an acid and it tastes sour.
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