pll :( Which of the following expresses the implied main idea of the article?

a. The borders between advertising and editorial content have blurred, but this is the price online newspapers have to accept because ad dollars pay for journalists and facilities.

b. The borders between advertising and journalism have blurred with the advent of the internet, and although this is an unfortunate trend, reputable journalism is still available.

c. The borders between advertising and journalism have become dangerously blurred, and steps must be taken by the Federal Trade Commission, editorial teams, and readers to reverse this trend.