Inference from Community Centers and Crime Rates

A study on crime rates in urban areas has concluded that cities with more community centers tend to have lower crime rates than those without. This finding prompted researchers to investigate further, leading them to examine the demographics of the neighborhoods surrounding these community centers. They found that neighborhoods with community centers often have a higher proportion of residents involved in community activities, which contributes to stronger social ties among neighbors.

Moreover, the researchers noted that other factors, including income levels and local law enforcement practices, were consistent across the cities studied but did not appear to influence the relationship between community centers and crime rates.

Based on the above information, which of the following statements must be true?