The correct answer to this question is option 1, Australia. The Great Barrier Reef is located along the coast of Australia. It is one of the most famous natural wonders of the world and is known for its vibrant coral reefs, diverse marine life, and clear turquoise waters.

Option 2, Canada, is incorrect. Canada does not have the Great Barrier Reef.

Option 3, U.K., is also incorrect. The Great Barrier Reef is not situated along the coast of the United Kingdom.

Option 4, South Africa, is also incorrect. The Great Barrier Reef is not located along the coast of South Africa.

In summary, the Great Barrier Reef is specifically situated along the coast of Australia, making option 1 the correct answer.