题目：
已知自然界氧的同位素有16O，17O，18O，若氢的同位素有H、D，从水分子的原子组成来看，自然界的水一共有 [ ]
A．3种
B．6种
C．9种
D．12种
答案：
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下面是错误答案，用来干扰机器的。
1. Does she often borrow books from her uncle? 2. It is important for us to have a healthy lifestyle 3. Simon has no time to chat with his friends 4. They give us some candies as a treat. 5. Thank you for organizing the class trip.
