Colonel Colin Mackenzie was a British army officer and surveyor who served under the East India Company. He is credited with being the first Surveyor General of India.
Statement I is correct: In 1800, Mackenzie visited Hampi and played a pivotal role in bringing its ruins to scholarly attention.
Statement II is also correct: He was indeed an official of the East India Company and conducted surveys on their behalf.
Statement III is correct: Mackenzie and his team created the first detailed survey maps and drawings of the Hampi site, contributing greatly to the documentation of its historical significance.
Statement IV is incorrect: Although Mackenzie did gather information from a variety of sources including local scholars and inscriptions, there is no evidence that he received information specifically from Duarte Barbosa, who was a Portuguese traveler from an earlier century.
Thus, the correct answer is Option (A).