Answer:
Using source materials to support view points is very important.
Step-by-step explanation:
A writer conducts research to gather information and writes on a variety of topics. Evaluating source materials gives writer a chance to decide what is correct and should be believed in. The correct use of sources also provides credibility to a viewpoint. It gives the writing an authority and writer can establish his point and influence the reader with the help of statistics, quotes and surveys.
The greater is the amount and variety of sources, the writing will be more persuasive.