Concept:The Ibadan Conference of 1950 was a political meeting held to deliberate on a new constitution for Nigeria.Explanation:In 1948, Sir John Macpherson became the Governor of Nigeria.He decided to review and replace the Richards Constitution of 1946.He therefore convened the Ibadan Conference in 1950 for this purpose.The conference discussed proposals that later led to the Macpherson Constitution of 1951.Answer:The Ibadan Conference of 1950 was convened to discuss the provisions of the Macpherson Constitution.Correct option: B. Macpherson Constitution.