Question

great barrier reef conservation
the great barrier reef, located off the coast of queensland, australia, is the worlds largest coral reef system. spanning over 2,300 kilometers, it consists of 2,900 individual reefs and 900 islands. this vibrant ecosystem supports diverse marine life, including thousands of fish species, coral formations, and marine mammals. however, climate change, pollution, and overfishing pose significant threats to its health.
major damaging factors to the great barrier reef
which phrase from the passage best represents the main idea?
a the great barrier reef, located off the coast of queensland, australia, is the worlds largest coral reef system
b this vibrant ecosystem supports diverse marine life, including thousands of fish species, coral formations, and marine mammals.
c rising global temperatures also trigger coral bleaching, a process where coral expel algae and turn white
d efforts to protect and preserve the reef are crucial for maintaining its biodiversity and supporting the livelihoods of local communities.

Explanation:

The passage starts by introducing the Great - Barrier Reef as the world's largest coral reef system. This is the over - arching fact that sets the context for the rest of the information about its ecosystem and threats. Options B, C, and D focus on parts of the reef's ecosystem, threats, and conservation respectively, but not the main idea which is the reef's significance as the world's largest coral reef system.

Answer:

A. The Great Barrier Reef, located off the coast of Queensland, Australia, is the world's largest coral reef system