大全12、
A little under a million years ago, the briny waters of the Baltic Sea began flooding into the cold North Atlantic: geologists are still debating whether the flood was gradual or created a cataclysm.
(A) whether the flood was gradual or created a cataclysm
(B) if the flood was gradual or created a cataclysm
(C) about whether the flood was gradual or cataclysmic
(D) whether the flood was gradual or cataclysmic（D）
(E) whether the flood was gradual or it created a cataclysm
C和D的唯一的区别在于C多了一个debate，但是我今天查了牛津双解词典（手上暂无其他词典），用法说debate (about) sth，并举了几个例子 what are they debating (about)? / we're just debating what to do next./ they debated closing the factory.
我想请问的是：此题是因为简洁的需要才选D的，还是说debate about的用法是错误的呢？有没有大牛能帮我看看debate的用法呢？谢谢！ | 
