definitive estimate

You are in the test phase of your software project, and the project sponsor has requested a definitive estimate of when your project will be completed. The most likely estimated duration is 30 days. Which of the following duration estimations will you give to your sponsor?

  1. 29 - 31 days
  2. 24 - 36 days
  3. 20 - 40 days
  4. 15 - 45 days

This could be 29 to 31 days

 It looks like you have considered -5 to +10 percent. The reason I have posted this question is , in PMBOK, though not mentioned as Definitive estimate explicitly, the range is given as -10 to +10 %. The same is case in RITA's book too

 

Hence need clarification whether to take -5 to +10 % or -10 to + 10 %?