What is the test for overturning a jury's verdict in a sexual assault case?

A reviewing court will not reverse a jury's verdict under state or federal law solely because it would have reached a different result if it had been the fact finder. (Vazquez, supra, 178 Cal.App.4th at p. 352; Jackson v. Virginia, supra, 443 U.S. at pp. 418-419.) "'Before a judgment of conviction can be set aside for insufficiency of the evidence to support the trier of fact's verdict, it must clearly appear that upon no hypothesis whatever is there sufficient evidence to support it.' [Citation.]" (People v. Kwok (1998) 63 Cal.App.4th 1236, 1245; see also People v. Kraft (2000) 23 Cal.4th 987, 1053-1054.)

It is a well-recognized legal principle that the testimony of a single witness is sufficient to prove a disputed fact unless the testimony is inherently improbable or physically impossible. (People v. Young (2005) 34 Cal.4th 1149, 1181; People v. Scott (1978) 21 Cal.3d 284, 296.)