So quickly are science and technology advancing  is a possibility today may be a reality tomorrow. 

A：when

B：which

C：what

D：that

A：What

B：Who  

C：Whatever

D：Whoever

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B：what

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D：where

A：Whenever

B：Whatever

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D：However

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A：If; what

B：Whether; that

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D：Whether; what

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B：why

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D：how

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B：When

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D：Whether

A：Whether

B：What

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D：How

A：anyone

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C：whoever

D：whomever