What is self-concept?

Self-concept refers to the comprehensive understanding and perception that individuals have of themselves, encompassing their abilities, beliefs, ideas, feelings, and overall self-image. It influences how we categorize ourselves, including our self-esteem and self-identity.

The reasoning behind B being the correct answer lies in its focus on the beliefs and definitions through which a person understands who they are. This set of abilities and opinions serves as a framework for individuals to evaluate themselves, impacting their motivation, behavior, and interactions with others.

The other options discuss elements that might influence or relate to one's self-concept but do not encapsulate its full definition. For instance, a group of friends with shared interests might contribute to one's social identity but does not define self-concept in its entirety. Similarly, measuring physical appearance is a more superficial aspect and does not encompass the broader, cognitive aspects involved in a person's understanding of themselves. The total sum of knowledge one possesses is also an external measurement and does not capture the subjective and personal nature of self-concept. Therefore, B provides the most accurate definition of self-concept as it recognizes it as a collection of personal beliefs and attitudes that shape one's identity.