The chief executives of Meta, Snap, Discord, X and TikTok testified on Wednesday in a Senate hearing about online child safety. Lawmakers have at least six bills waiting in the wings about the issue.

Senator Richard Blumenthal, left, and Sam Altman, chief executive of OpenAI, at a hearing on artificial intelligence in May. Mr. Blumenthal and Senator Josh Hawley, Republican of Missouri, plan to announce a sweeping framework to regulate A.I.