Concept:Federalism means a system where power is shared between a central government and regional governments.
Explanation:The Lyttelton Constitution of 1954 formally introduced federalism in Nigeria.
It divided powers between the central government and the regions.
This arrangement gave the regions a degree of autonomy.
Earlier constitutions, such as the Richards Constitution, only created regions without real federal powers.
Thus, the 1954 Lyttelton Constitution marked the beginning of true federal governance in Nigeria.
Answer:A. Lyttelton Constitution