The correct answer is D. hesitate.

To hesitate is to pause or delay in doing something, especially because of doubt or uncertainty. In the context of the question, if you waver at the last minute, you will be hesitant to take action, which will likely lead to failure.

The other options are incorrect because they do not convey the meaning of hesitation.

  • Resolve means to make a firm decision to do something.
  • Decide means to come to a conclusion about something.
  • Settle means to come to an agreement or arrangement.

If you are hesitant, you are not making a firm decision, coming to a conclusion, or coming to an agreement. You are simply delaying in doing something.