What is the test for a jury to convict a defendant on a charge of aiding and abetting a murder?

But the prosecution advanced two theories of liability for murder: the natural and probable consequence doctrine, and aiding and abetting. Prosecutors are allowed to argue alternative theories, and we may affirm on either theory if it is sufficiently supported. "Ordinarily, if an alternative theory of criminal liability is found unsupported by the evidence, the judgment of conviction may rest on any legally sufficient theory unaffected by the error, unless the record affirmatively demonstrates that the jury relied on the unsupported ground." (People v. Sanchez (2001) 26 Cal.4th 834, 851.)