Which of the following best describes racial profiling?

Racial profiling is most accurately defined as the reliance on race or ethnicity in law enforcement decisions, which is why this option is the best choice. It involves law enforcement making determinations about an individual's likelihood of committing a crime based primarily on their race or ethnicity rather than on objective evidence or behavior. This practice is widely criticized because it can lead to discrimination and a violation of individuals' civil rights.

In contrast, making decisions based solely on criminal background does not take into account race or ethnicity and focuses instead on an individual’s past actions, which is not racial profiling. Using behavior as a factor for decisions emphasizes the importance of observable actions rather than demographic characteristics, which again is not aligned with the definition of racial profiling. Finally, relying on public opinion for decisions does not inherently involve race or ethnicity and instead points to societal perceptions that can often be misguided or inaccurate, but it does not define the practice of profiling based on race.