What is the test for a criminal defendant to successfully appeal against his conviction for sexual assault?

[Citation.]" (People v. Sanghera (2006) 139 Cal.App.4th 1567, 1573.) "Perhaps the most fundamental rule of appellate law is that the judgment challenged on appeal is presumed correct, and it is the appellant's burden to affirmatively demonstrate error. [Citation.] Thus, when a criminal defendant claims on appeal that his conviction was based on insufficient evidence of one or more of the elements of the crime of which he was convicted, we must begin with the presumption that the evidence of those elements was sufficient, and the defendant bears the burden of convincing us otherwise. To meet that burden, it is not enough for the defendant to simply contend, 'without a statement or analysis of the evidence, . . . that the evidence is insufficient to support the judgment[] of conviction.' [Citation.] Rather, he must affirmatively demonstrate that the evidence is insufficient." (Ibid.)

b. Elements of the charged offense.