Question

a malignant neoplasm composed of parafollicular cells(c - cells) in the thyroid gland will most likely present with signs and symptoms consistent with: a compensatory decrease in parathyroid hormone activity an increased rate in basal metabolism hypocalcemia resulting in a decrease in calcium mediated activity decreased metabolism, cold intolerance, edema, increased catecholamine sensitivity

Explanation:

Parafollicular cells (C - cells) of the thyroid gland secrete calcitonin. Calcitonin lowers blood calcium levels. A neoplasm of these cells can lead to excessive calcitonin secretion, causing hypocalcemia which results in decreased calcium - mediated activity. Parathyroid hormone activity is not directly related in this context. Increased basal metabolism is related to thyroid hormones from follicular cells, not C - cells. Decreased metabolism, cold intolerance etc. are symptoms of hypothyroidism related to thyroid hormone deficiency from follicular cells.

Answer:

C. hypocalcemia resulting in a decrease in calcium mediated activity