We have the technology to digitally sign, media (video, sound and text). Articles and media could be signed and validated the same way that your web browser can verify if the web site you're viewing has a valid signed certificate. This would mean that facebook or even your browser could detect if a media is from a trusted source.
The trusted sources (main stream media) could then decide to embed advertisement in their media that couldn't be removed without destroying the trusted signature. Further, with this signature, computers could easily track which article gets flagged as inaccurate or even fake which could impact a "trusted source" credibility rating.
In essence I'd propose a system that would give an incentive for trusted media to validate their stories and sources so their credibility levels don't get destroyed, while having the ability to generate revenues for their stories instead of the main search engines and social media power houses.