What is the standard of review on appeal from a judgment dismissing an action after sustaining a demurrer without leave to amend?

"On appeal from a judgment dismissing an action after sustaining a demurrer without leave to amend, the standard of review is well settled. The reviewing court gives the complaint a reasonable interpretation, and treats the demurrer as admitting all material facts properly pleaded. The court does not, however, assume the truth of contentions, deductions or conclusions of law. The judgment must be affirmed if any one of the several grounds of demurrer is well taken. However, it is error for a trial court to sustain a demurrer when the plaintiff has stated a cause of action under any possible legal theory. . . ." (Aubry v. Tri-City Hospital Dist. (1992) 2 Cal.4th 962, 966-967; citations and internal quotation marks omitted.)