Final answer:
Extroversion is the trait described as a tendency to be sociable, assertive, and active, often seen in individuals who are outgoing and energized by social interaction.
Step-by-step explanation:
The trait that represents a tendency to be sociable, assertive, and active is B) Extroversion. Whereas neuroticism is associated with emotional instability, and conscientiousness with being hardworking and dependable, extroversion is characterized by sociability and warmth. This tendency plays a significant role in how individuals interact with the world around them, especially in social settings. People with high levels of extroversion are considered outgoing and are often energized by engaging in social interactions.