How did european exposure to infectious diseases actually become an advantage

Which best explains why the supreme court’s decision in plessy v. ferguson was unconstitutional? the supreme court’s ruling allowed states to deny equal protection to any person within its jurisdiction. since the 14th amendment did not make concessions for people born outside the us, the supreme court’s decision could not be applied. the supreme court’s decision gave individual states the freedom to make their own laws in relation to non-whites. since segregation laws did not provide equal protections or liberties to non-whites, the ruling was not consistent with the 14th amendment.