Too high house prices can be brought under control，____the authorities introduce a series

of regulatory policies．

A．even if

B．as if

C．so that

D．provided that

施工承包商与分包商签订的合同、安全协议必须遵循施工承包合同的各项原则，满足承包合同中的技术、（）、承包双方的权利和义务等