The medical record shows that it was the drug, not the disease, ________ killed him two years ago.
句意：医疗记录表明是两年前是药而非疾病夺去了他的生 命。考查强调句。在shows后面的那个宾语是这个强调句，格式是it is ...that ....。题目就是 it was the drug that killed him two years ago。如果去掉 it is ...that 的话，这个句子的结果仍是完整的，就是一个强调句。所以答案选D。