A sentence has been given in Active/Passive voice. Out of the four alternatives suggested below, select the one which best expresses the same sentence in Passive/Active voice. 
 

I shall write a book.  

 A book will be written by me.

A book will be written by me.

Explanation:

• A book is written by me.: This passive construction correctly reverses the subject and object but changes the tense from future ("shall write") to present ("is written").
• A book will be written by me.: This passive construction correctly reverses the subject and object while maintaining the original future tense.
• A book has written to me.: This active construction changes the subject from "I" to "a book" and introduces a different action ("written to me") which is not present in the original sentence.
• A book has been written by me.: This passive construction changes the tense from future ("shall write") to present perfect ("has been written"), which doesn't accurately match the original meaning.