Answer:
Having a clear-cut procedures for dissemination of reports or information to the public.
Step-by-step explanation:
What best describes why main stream might be called more accountable or responsible for reports is by making use of clear-cut procedures or reliable source of information, for fact-checking and consequences for breaking these rules.
This enables the validity of the the information reported or given out. If for example, instance you are reporting on a recent events of a statement made by politician , do not take this information from other sources like yahoo page, or Nairaland page or other sources.