Final answer:
The symptoms described by the student, including increased urinary output, nausea, and abdominal pain, suggest the condition of hypercalcemia. This condition causes an underactive nervous system, leading to a range of symptoms similar to those reported.
Step-by-step explanation:
The manifestations mentioned by the student, which are increased urinary output, nausea and vomiting, reports of thirst, abdominal pain, constipation, drowsiness, and headaches, are indicative of A) Hypercalcemia. In hypercalcemia, the body's nervous system becomes underactive, leading to symptoms such as lethargy, sluggish reflexes, constipation, loss of appetite, and confusion. If hypercalcemia is severe, it can even progress to coma. These symptoms align with the ones mentioned in the question, as opposed to the other conditions listed that are associated with different sets of symptoms.