The operation room in every hospital has to _______bacteria of any kind so that the patient being operated on doesn’t get infected.

A．keep free from

B．make it free from

C．to be made free with

D．be kept free from

报关企业如需要在注册登记许可区域外(即另一直属海关关区)从事报关服务的，应当依法设立分支机构，并且向直属海关递交报关企业分支机构注册登汜许可申请。