What is the ultimate source of food for animals living around deep-sea hydrothermal vents?

A) sunlight and photosynthesis
B) the decay of creatures that float on the ocean surface and settle to the bottom
C) nuclear energy from the heated uranium-rich rocks
D) bacteria that break down hydrogen sulfide

The ultimate source of food for animals living around deep-sea hydrothermal vents is bacteria that break down hydrogen sulfide. These bacteria are chemosynthetic, meaning they can produce organic compounds using energy derived from chemical reactions, unlike photosynthesis, which uses sunlight. This allows life to thrive in the dark environments of deep-sea vents, where sunlight cannot reach.