A being reported B it was reported C was reported D to be reported
答：C
譯：爆炸中傷亡人數比報道的更多。
分析：than引導的比較狀語從句常省略。這裏省略了主語what
= than what was reported
細看題句還是有問題的，不知道more casualties與什麽在比較。
其實用than reproted最好了，即有省略，又避免其中的語法問題（什麽和什麽比較，省略了什麽?主謂壹致？）
請看這裏老外的解釋：
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