(20 points) why did it take so long for christian kingdoms in northern spain to expel non-christian people from the iberian peninsula? a. there wasn't much of a desire to expel non-christian people, as many were good for the economy. b. most were too focused on exploration, and weren't concerned with expelling muslim forces. c. many of the christian kingdoms in the north were divided and weak. d. they were busy fighting the hundred years' war.