What are the legal principles applicable to a challenge to the sufficiency of the evidence to sustain a conviction?

The legal principals applicable to a challenge to the sufficiency of the evidence to sustain a conviction are set out ante, at pages 39 through 40. While a jury may not rely on unreasonable inferences, and an inference is unreasonable if it is based only on speculation (People v. Hughes (2002) 27 Cal.4th 287, 365), " '[c]onflicts and even testimony which is subject to justifiable suspicion do not justify the reversal of a judgment, for it is the exclusive province of the trial judge or jury to determine the credibility of a witness and the truth or falsity of the facts upon which a determination depends. [Citation.] We resolve neither credibility issues nor evidentiary conflicts; we look for substantial evidence.' [Citation.]" (People v. Lee (2011) 51 Cal.4th 620, 632.)