22.Lawrence Craven, a doctor from the USA,is the author of several published reports, one of______ introduced the idea in 1953 ______aspirin could reduce the risk of heart attacks. A.them; when B.which; that C.what; that D.which; when
答案:B 解析: 考查从句。第一个空考查定语从句,which 用于介词后指代前文的reports。第二个空是由that引导同位语从句。具体说明idea的详细内容。