A child could not have done this mischief. Change into passive voice--

Question: A child could not have done this mischief. Change into passive voice--

A) This mischief could not have been done by a child.

B) This mischief could not been done by a child.

C) This mischief could not have be done by a child.

D) This mischief a child could not have been done.

Answer:
A) This mischief could not have been done by a child.

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We will not admit children under ten.