The correct answer is C. California.
Redwood trees are native to the coastal forests of California. They are the tallest trees in the world, with some reaching heights of over 380 feet. Redwood trees are an important part of the California ecosystem, providing habitat for many different species of plants and animals. They are also a popular tourist attraction, with many people visiting Redwood National Park and other redwood forests each year.
Option A is incorrect because Australia is not home to any redwood trees. Option B is incorrect because the Amazon rainforest is home to a variety of different tree species, but redwood trees are not among them. Option D is incorrect because Thailand is also not home to any redwood trees.
I hope this helps! Let me know if you have any other questions.