The correct answer is option 1 - Colonel Colin Mackenzie. In 1800, Colonel Colin Mackenzie was the one who brought to light the ruins of the Vijayanagara at Hampi. Colonel Mackenzie was a British army officer and a surveyor who had a keen interest in archaeology. He served in the British East India Company and was appointed as the first Surveyor General of India.

During his time in India, Colonel Mackenzie conducted extensive surveys and documentation of historical and archaeological sites. He had a particular interest in the Vijayanagara Empire and its capital, Hampi. His exploration and documentation efforts played a vital role in bringing recognition to the rich history and architectural wonders of Vijayanagara.

Through his meticulous surveying and research, Colonel Mackenzie was able to uncover and reveal the magnificence of the ruins at Hampi. His efforts helped shed light on the grandeur and significance of the Vijayanagara Empire, which was one of the most powerful and prosperous South Indian empires in history.

Overall, the credit for bringing to light the ruins of the Vijayanagara at Hampi in 1800 goes to Colonel Colin Mackenzie, whose passion for archaeology contributed greatly to our understanding of this ancient civilization.