Question

what is the central idea of this selection?
a tarbells work with newspapers and magazines helped with the formation of labor unions.
b tarbells experience with oil fields made her the perfect person to bring legal action against standard oil.
c tarbell was a gifted writer, but her prejudices toward successful companies made her a biased critic.
d tarbell used journalism to educate the public and expose illegal or unethical practices.

Explanation:

To determine the central idea, we analyze each option:

• Option A: There's no indication her newspaper work helped form labor unions, so this is incorrect.
• Option B: The focus isn't on her being the "perfect person" for legal action against Standard Oil, but on her journalistic work, so this is wrong.
• Option C: The idea of her being a "biased critic" due to prejudices isn't supported; she was an investigative journalist exposing unethical practices, so this is incorrect.
• Option D: Ida Tarbell was a muckraking journalist who used her work to inform the public and reveal illegal/unethical business practices (like those of Standard Oil), so this aligns with her role.

Answer:

D. Tarbell used journalism to educate the public and expose illegal or unethical practices.