The self Concept is the competency perspective -best encompasses Bob's weakest leadership competency .
Explanation:
Self-concept refers to one's own thought of ones perception or the individual perceptions on his own behavior, abilities, and unique characteristics—in simple words it refers to a mental picture of who you are as a person.
For example, beliefs such as "I am a good teacher" or "I am a intelligent person" can be said to be a part of an overall self-concept.
In the question given above Bob is worried about his his ability to take on twice as many employees and continue on a successful path.So,this reflect the Self Concept perspective of Bob's personality
Hence the answer is (a) Self -Concept