According to Moses in the book of Deuteronomy, God was giving the land of Canaan to the Israelites primarily because the people who were currently living in the land were very wicked and needed to be punished. This rationale is echoed throughout the text, where it is indicated that the wickedness of the Canaanites was a significant factor in their being displaced. Thus, the correct answer is:
because the people who were currently living in the land were very wicked and needed to be punished.