Concept: The south-western part of Ghana lies in a high-rainfall region, which supports dense forest vegetation.Explanation:• South-western Ghana receives heavy and well-distributed rainfall throughout the year.• This climate favours the growth of tall trees with thick canopies, which is characteristic of the tropical rain forest.• The other vegetation types, such as coastal grassland, guinea savanna, and mangrove forest, are found in drier or coastal/wetland areas, not the south-western forest zone.Answer: A. rain forest.