Answer:
A). Jet lag.
Step-by-step explanation:
Jet lag exemplifies a physiological condition in which there is a temporary sleep problem that occurs due to variance in circadian rhythms. It may affect the people who travel across varied time zones. In the given question, Mona displays 'Jet Lag' disorder as she has trouble sleeping as her internal body clock(circadian rhythm) is still fixed to the time zone of California instead of her present location and time zone. Thus, her body is unable to adjust to the new time zone and experiences 'Jet lag' disorder. Hence, option A is the answer.