Which of the following is a tip for optimizing a TrueView video ad campaign?

Q) Which of the following is a tip for optimizing a TrueView video ad campaign?
  A)  Remove all but one targeting group from the campaign.
  B)  Add exclusions to the campaign or targeting group.
  C)  All of the listed answers are incorrect.
  D)  Increase each target group’s bid by 100%.