B and A look like good answers, but the meaning of candor is "unbiased, impartial"; and although that seems like a good answer it is not because the question does <em>not</em> ask you about a quote that talks of <em>entering</em> an argument, simply <em>being</em> in it. So, I would definitely say that the answer is A. :)
<span>D. see whether you have included all the information in the right place</span>
