Final answer:
The medical student likely suffers from Specific Phobia, a condition characterized by irrational fear and anxiety triggered by a specific stimulus, in this case, lizards.
Step-by-step explanation:
The most likely diagnosis for the 25-year-old medical student who experiences uncontrollable panic, a rapid heartbeat, difficulty breathing, intense anxiety, and helplessness whenever she sees a lizard is a) Specific Phobia. These symptoms suggest that she has an irrational and excessive fear of a specific object, situation, or living creature - in this case, lizards. This condition is characterized by intense anxiety or panic attacks triggered by the presence or anticipation of the specific feared object or situation. The response she has been experiencing, including the physiological reactions such as a racing heart, rapid breathing, and feeling of terror, aligns with how the body prepares to either defend itself or flee from what is perceived as danger. This is part of the fight-or-flight response, heavily