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Re: It is difficult to provide _______ proof for the existence
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03 Oct 2017, 11:38
Explanation
Since ghosts are described as unseen by the majority, it must be difficult to provide visible or definite proof. Indisputable and demonstrable both convey the meaning you want, and produce equivalent, appropriate sentences.
Choice (D) means important. Choice (B) means intimidating and choice (C) means mysterious. Skeptical may be a good word to describe those who don’t see the ghosts, but it can’t describe the proof.
Hence options A and F are correct!