During the first Republican presidential debate of 2015, one of the candidates said, "The purpose of the military is to kill people and break...

B is not the correct answer here.  Framing happens when the media influences the way people think about an issue.  If a media commentator had said what this candidate said, we could say that they were engaged in framing.  But this was something that a candidate said so it cannot be framing.

It is more accurate to call this a sound bite.  A sound bite can be defined as a very short snippet that is spoken by a candidate.  It is meant to convey something about the candidate’s position in a very short time.  Because it is meant to be short, it cannot really be very in-depth or complex.  It has to be a very simplistic exposition of a point of view.

The quote that you give here meets this definition.  It is a very brief statement of the candidate’s opinion that really cannot be very complex or in-depth.  Instead it is more like a short slogan that the candidate thinks will help him in the election.  Therefore, I would call this a sound bite rather than an example of framing.