Which one of the following is NOT a significant property of attitude?

The correct option is Quantity.

In social psychology, an attitude is a psychological tendency that is expressed by evaluating a particular entity with some degree of favor or disfavor. Attitudes have several significant properties or dimensions that define their structure and influence on behavior:
1. Valence (or Direction): This refers to whether an attitude is positive, negative, or neutral toward the attitude object. It indicates the direction of the evaluation.
2. Extremeness: This indicates how strong the positive or negative attitude is. For example, a person can have a moderately positive attitude or an extremely positive attitude toward an object.
3. Centrality: This refers to the role or importance of a particular attitude in the person's overall attitude system. Central attitudes are highly important to the individual and influence other dependent attitudes.
4. Complexity (or Multiplexity): This refers to the number of elements or beliefs that make up the attitude.

Among the given choices, Quantity is not a recognized psychological property or dimension of attitude. While attitudes have strength and intensity, they are qualitative evaluations and are not measured in terms of physical or numerical "quantity." Therefore, Quantity is the correct answer as it is NOT a significant property of attitude.