It _______ law for some people to let the children who are not old enough ____   in the factories for them.

A．goes against; to work

B．goes against; work

C．sets against; to be working

D．sets against; working

青春前期牙周炎的发病特点，哪一项不准确

A．外周血中性粒细胞或单核细胞功能低下
B．牙周破坏速度快，牙齿松动
C．只累及乳牙
D．牙龈炎症程度不同，可有深牙周袋
E．可伴有中耳炎及其他感染