Which factor indicates how strongly people hold various beliefs around a political issue?

The factor that indicates how strongly people hold various beliefs around a political issue is intensity. Intensity refers to the depth of feeling or conviction that individuals have regarding an issue. When people have a strong intensity of belief, they are more likely to express their opinions fervently and take action based on those beliefs, demonstrating a high level of emotional investment. For example, a highly intense belief about climate change may lead individuals to participate in protests, advocate for policies, or engage in significant efforts to support environmental causes.

In contrast, the other factors relate to different aspects of political beliefs: stability refers to the consistency of those beliefs over time; direction indicates whether people's beliefs are positive or negative towards an issue; and salience relates to the relevance or importance of an issue to individuals or groups. While all these factors are important in understanding public opinion, intensity is specifically about the strength with which beliefs are held, making it the correct choice in this context.