How is an attitude characterized by distrust in others' motives best described?

The characterization of an attitude marked by distrust in the motives of others is best described as cynicism. Cynicism entails a belief that people's actions are motivated primarily by self-interest, leading individuals to view the intentions and behaviors of others with skepticism. This perspective often results in assumptions that others are not acting with good intentions, which aligns with the notion of distrust.

In contrast, pessimism typically refers to a general negative outlook on life or anticipation of unfavorable outcomes, while realism focuses on perceiving situations as they are, often lacking the distrust component inherent in cynicism. Optimism, on the other hand, represents a hopeful or positive outlook regarding future events or the motivations of others, which contradicts the essence of cynicism. Therefore, cynicism is the most accurate term to describe an attitude rooted in distrust towards the motives of others.