What is the objective test in determining whether a criminal act was a natural and probable consequence of another criminal act?

An objective test is used in determining "whether a particular criminal act was a natural and probable consequence of another criminal act." (People v. Nguyen (1993) 21 Cal.App.4th 518, 531.) "Consequently, the issue does not turn on the defendant's subjective state of mind, but depends upon whether, under all of the circumstances presented, a reasonable person in the defendant's position would have or should have known that the charged offense was a reasonably foreseeable consequence of the act aided and abetted by the defendant." (Ibid.) "A natural and probable consequence is one that a reasonable person would know is likely to happen if nothing unusual intervenes." (CALCRIM No. 402.)