Reggie is un-interesting, dull, and humorless. He is aloof and reclusive, rarely responds to people saying "Good morning" or "Hello" to him, and often doesn't understand jokes. His self-concept is distorted, and he has difficulty understanding others’ motives. If Reggie were diagnosed with a personality disorder, it would most likely be:.a. antisocial personality disorder. b. narcissistic personality disorder. c. schizotypal personality disorder. d. borderline personality disorder.

c) Schizotypal personality disorder.

Explanation:

Schizotypal personality disorder is the disorder related with mental and personality health in which a person tends to behave strangely, faces social anxiety, strange and distorted  thoughts etc.

According to the question,if Reggie has dull, non-social and humorless personality then it might be due to fear with social situation and persistence of strange thought.Thus, she might have schizotypal personality disorder

Other options are incorrect because narcissistic personality disorder ,antisocial personality disorder and borderline personality disorder are not the personality disorder .This,the correct option is option(c).

answer; direct observation;