Which best describes the role of a tiny plant in a coral reef ecosystem?

In a coral reef ecosystem, tiny plants, particularly zooxanthellae (symbiotic algae), play a crucial role by providing essential nutrients to coral through photosynthesis. They convert sunlight into energy, which supports coral growth and resilience. This symbiotic relationship helps maintain the health of the reef, promotes biodiversity, and supports various marine species that rely on the coral for habitat and food. Without these tiny plants, the entire reef ecosystem would struggle to thrive.