Which one is NOT true about quarantine laws?
A.Authorities put rules in place to try to prevent plague from spreading in the first place
B.Related department isolated ships, passengers, and cargo if the ship was suspected of carrying plague
C.Even when the system worked perfectly, it could not stop rats and fleas.
D.Quarantine laws were not enough to save half of the people of marseilles in 1720.48
E.Quarantine laws was useless actually
正确答案是E