Final answer:
Option A). The symptoms described are indicative of an anxiety disorder, which is the correct answer to the student's query. Anxiety can produce a range of physical symptoms, and managing stress is important for symptom relief.
Step-by-step explanation:
Anxiety disorders are linked to the distinctive symptoms listed in the student's question, which include a faster heartbeat, perspiration, elevated blood pressure, muscle aches, intestinal pains, irritability, trouble sleeping, and difficulty concentrating. While some of these symptoms can also be found in other conditions, such as cardiovascular diseases and thyroid disorders (such as hyperthyroidism or hypothyroidism), the particular combination and context given point to an anxiety-related problem. Because anxiety disorders trigger the body's flight-or-fight response, they can cause a wide range of physical symptoms. Reducing stress is essential to easing these symptoms.
Therefore, the correct answer to the fill-in-the-blank question is a) Anxiety disorder.