Which of these factors or groups is most likely to shape public opinion on a range of political issues?

I don't know what options you had available but here are some ideas: 1) Journalists: since journalists present the information and compose articles that people write, they have an influence over people's political issues 2) celebrities - people very often trust celebrities because they can identify with them 3) authority figures - because people believe their judgements are well informed

Not a question but you !