Name the Australian region known for its tropical rainforests.

The Daintree Rainforest is recognized as one of the oldest tropical rainforests in the world, making it a significant area of biodiversity and ecological importance in Australia. This region, located in Queensland, is part of the Wet Tropics World Heritage Site and features a unique combination of flora and fauna, many of which cannot be found anywhere else on the planet. The Daintree is characterized by its rich variety of plant species, ancient trees, and diverse wildlife, including species like the cassowary and tree kangaroos. This rich ecological background and the fact that it is classified as a tropical rainforest establishes the Daintree Rainforest as the correct answer to the question.

In contrast, the Blue Mountains are known for their dramatic scenery and eucalyptus forests, the Flinders Ranges are a mountain range with a more arid landscape and significant geological formations, and the Great Dividing Range is a major mountain range that stretches down the eastern coast of Australia, but none of these areas feature the same tropical rainforest conditions that define the Daintree. Hence, the Daintree Rainforest stands out as the quintessential tropical rainforest region in Australia.