Concept:The Lyttelton Constitution of 1954 is recognised as the foundation of Nigeria’s federal system of government.Explanation:Before 1954, Nigeria operated largely as a unitary or quasi-federal state.The Lyttelton Constitution introduced a true federal structure, dividing the country into regions with a central federal government.This made it a landmark because it formally established federalism in Nigeria.Although Lagos was also made a federal territory, the main landmark achievement was the creation of the federal structure.Answer:A. created a federal structure of government for the country