Which group was responsible for initially capturing the slaves?

It is estimated that more than half of the entire slave trade took place during the 18th century, with the British, Portuguese and French being the main carriers of nine out of ten slaves abducted in Africa.

you didn't give any answers to choose from so i can't with this but, i do know something that the mexican government would be worried about and that is the wall that donald trump is currently trying to get up.