题目内容:
Whatdowelearnfromthelastparagraph?
A.Scientistsareplanningtoinstallpipesinallcraterlake B.Scientistsstilldonotknowhowtopreventgasexplosions
C.Explosiondisasterscouldbeavoidedinthefuture
D.Warningsystemshavebeensetupinthevillagesnearby
参考答案:
答案解析: