PART A: Which of the following identifies a central idea of the text?

A
News media has evolved to include a range of sources, but it continues to play an important role in informing citizens and holding public officials accountable.
B
News media can be a valuable resource for learning about current events, but it is impossible to determine whether information is unbiased.
C
News media has shifted to consist mainly of online sources, which makes checking the validity of a source difficult.
D
News media provides unprejudiced information to the people, which allows them to remain informed and hold those in power accountable for their actions.