The Research Cited by the Text Authors Regarding Population-Based Intervention

The research cited by the text authors regarding population-based intervention efforts has suggested that:

A) reaching out to patient populations is expensive and has mixed results.
B) offering services proactively can reach a greater number and more varied group of people.
C) most people are not willing to participate in any clinical services unless they are already in the contemplation stage of change.
D) as usual,those in the action stage benefited most.