Which of the following disorders is characterized by frantic efforts to avoid real or imagined abandonment?

The disorder characterized by frantic efforts to avoid real or imagined abandonment is Borderline Personality Disorder. Individuals with this condition often have an intense fear of being abandoned or rejected, leading to unstable relationships and emotional responses. This fear may prompt individuals to engage in behaviors aimed at preventing separation or loss. As a result, they may react strongly to perceived threats of abandonment, including idealizing those close to them, followed by sudden feelings of anger or emptiness when they feel unnoticed or neglected.

Borderline Personality Disorder is also marked by other symptoms such as identity disturbances, impulsivity, and extreme emotional fluctuations, but the core feature of abandonment fear is central to understanding the disorder. The other disorders listed do not primarily focus on abandonment as a defining characteristic; therefore, they do not capture the essence of the behavior described in the question.