Answer:
A) Bipolar Disorder.
B) DID (Dissociative identity disorder).
Step-by-step explanation:
DID is a mental illness characterized by, at least, two different and relatively stable states of personality. Patricia, who happens to miss periods of time, has another personality (according to this example) called Priscilla. Priscilla is different from her because she was "the life of the party", and Patricia doesen't drink, is shy and retiring. This could also mean that she has a bipolar disorder, which is characterised by depression and abnormal mood swings. That could explain why Patricia, a shy and retiring person, is also Priscilla, the life of the party.