Concept:Bays and headlands are coastal landforms formed by wave erosion and deposition along a coastline.Explanation:Bays and headlands occur where alternating bands of hard and soft rock meet the sea.Outcrops of resistant rock project into the sea as headlands, while the softer rock is eroded faster to form bays.In Nigeria, these features are found along the Southern Coastlands, which border the Atlantic Ocean.The other regions (North Central Highlands, Sokoto Plains, Eastern Scarpland) are inland and not associated with coastal features.Answer:A. Southern Coastlands