Solution: Chemosynthetic bacteria are organisms that use inorganic chemicals as a source of energy and convert them to organic compounds. They get their energy through the oxidation of inorganic chemicals rather than photosynthesis, unlike plants. Inorganic molecules such as ammonia, molecular hydrogen, sulfur, hydrogen sulfide, and ferrous iron are used by chemosynthetic bacteria to generate the organic compounds they require for survival. Chemosynthetic bacteria can be discovered in the deep sea or in places where sunlight is limited. So, the correct answer is (d).