What are the appellate courts' options when confronted with conflicting evidence on an unresolved question of fact?

Confronted with conflicting evidence on an unresolved question of fact, we have at least four options. First, in certain circumstances, appellate courts can infer the trial court impliedly resolved the question. However, appellate courts accept the existence of implied factual findings only if they are supported by substantial evidence. (See People ex rel. Dept. of Corporations v. SpeeDee Oil Change Systems, Inc. (1999) 20 Cal.4th 1135, 1143 [appellate court accepted trial court's implied findings that were supported by substantial evidence].) Here, the record before the trial court lacks substantial evidence contradicting the payment date listed in the register of actions. Therefore, we will not infer the trial court impliedly found the fees were paid with the filing.