I'm completing form I-90, and in one of the questions it asks me about my race. I'm Hispanic (Mexican), why is the system telling me to select white?

According to the U.S. Census, people of Hispanic origin may be of any race. In the 2010 Census, the Hispanic population predominantly identified as White. You may choose any race that applies to you, you may also choose more than 1 if necessary. CITATION: Page 5; http://www.census.gov/prod/cen2010/briefs/c2010br-02.pdf