What is the test for a plaintiff to argue that the trial court abused its discretion in denying them leave to amend their complaint?

Plaintiffs contend the trial court abused its discretion in denying them leave to amend, but they fail to provide an explanation how they could amend their complaint to overcome the defects discussed in this opinion. As explained above, a plaintiff may not assert an abstract right to amend; rather, a plaintiff must specify the additional facts it would allege and explain how those facts are sufficient to state a cause of action under the controlling legal authority. (Rosen, supra, 193 Cal.App.4th at p. 458.) Plaintiffs failed to do so, and therefore failed to establish an abuse of discretion. (Id. at p. 464; Rakestraw v. California Physicians' Service (2000) 81 Cal.App.4th 39, 53 [no abuse of discretion in denying leave to amend when appellants failed to "provide[] adequate legal authority or factual allegations . . . to satisfy their burden of showing that there is a reasonable possibility that they can amend the legal effect of their complaint"].)