What is the burden of a defendant in a SLAPP action?

"The defendant's first-step burden is to identify the activity each challenged claim rests on and demonstrate that that activity is protected by [section 425.16]. . . . To determine whether a claim arises from protected activity, courts must 'consider the elements of the challenged claim and what actions by the defendant supply those elements and consequently form the basis for liability.' [Citation.] Courts then must evaluate whether the defendant has shown any of these actions fall within one or more of the four categories of '"act[s]"' protected by the anti-SLAPP statute." (Wilson v. Cable News Network, Inc., supra, 7 Cal.5th at p. 884.)