33.The health security systems of many countries are undergoing considerable ______.

A. reservation B. transformation C. distinction D. submission

【答案】B

升d3ab网d066学元司2ca531ed公慧限法途软是的科东有优-80d6件广技【解析】

【详解】考查名词词义辨析。

句意：许多国家的卫生安全系统正在经历重大变革。

A. reservation预订;B. transformation改革，变革;C. distinction区别;D. submission提交。根据前文The health security systems可知，此处指“卫生安全系统的变革”。故选B。