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. 
 

You don't need to repair this watch.

This watch need not be repaired.

This watch need not be repaired.

Explanation:

• This watch need not be repaired.: This passive construction correctly maintains the original meaning and reverses the subject and object while using the appropriate verb tense.
• This watch does not repair.: This active construction introduces a different verb ("does not repair") and doesn't accurately convey the original sentence.
• This watch need not be repaired up.: This construction is grammatically incorrect and adds "up" which is not present in the original sentence.