What is the capital of Queensland?

Brisbane is the capital city of Queensland, which is one of Australia's six states. It is located in the southeastern corner of the state along the Brisbane River. The city serves as the administrative and economic center of Queensland, hosting the state parliament and various government institutions. Brisbane is also known for its vibrant cultural scene and is the third most populous city in Australia.

The other options presented are capitals of different regions; Melbourne is the capital of Victoria, Canberra serves as the capital of Australia itself (the federal capital), and Sydney is the capital of New South Wales. This distinction clarifies why Brisbane is the only correct answer when identifying the capital of Queensland.