The correct answer is C. The evidence textual offers the information to build the main idea. It also means that they are connected but they are different. The main idea has no sense without textual evidence. So, The main idea became the main idea because of the lack of textual evidence or the lack of pieces of information for that.
Persuade: To convince someone to do something without reasoning or an argument.
Example: The weather report persuaded me to stay home.
Answer: The contrast effect is a magnification or diminishment of perception as a result of previous exposure to something of lesser or greater quality, but of the same base characteristics.
