Answer:
Correct answer is a more than 250 ethnic groups.
Explanation:
A is correct as there are more than 250 groups, largest ones being Hausa, Yoruba, Igbo...
B is not correct as around half of population are city dwellers, and they are not all Muslims, but there are many Christians.
C is not correct because as we have said in option A there are more than 250 of them.
D is not correct as while Hausa are representing around 27 percentage, there are no English practically.
