Im a story who is the protagonist

The protagonist is the person who is causing change in a story and is usually the main character.

So it's the main person that the story is about.

The protagonist is the center of the story and usually faces difficult obstacles in order to cause change or seek a goal.

Yes, because it is run by a governmental organization. Option C is correct.

Since the United States Centers for Disease Control website is run by the government, Tori will find and gather from there really truthful, accurate and reliable information for the purpose of supporting the main topic of her post about how wearing sunblock can help prevent skin cancer.

Usually, information posted on websites of the government or important organisations or bodies such as UN, will present useful and reliable information.