Read this piece of evidence from the article "School Violence: Why Prevention Must Be a Priority.” Violence costs the United States an estimated $425 billion in direct and indirect costs each year. Of these costs, approximately $90 billion is spent on the criminal justice system, $65 billion on security, $5 billion on the treatment of victims, and $170 billion on lost productivity and quality of life.

What would be the most reliable way to verify these numbers?
Select one:
a. Write to the author to request more detailed references to the source.
b. Find other articles that cite the same primary source of information.
c. Try to find the information in an encyclopedia or a dictionary.
d. Check the information in the source that the author has cited.
Clear my choice