Answer: option C - hypoparathyroidism
Explanation:
Insufficient secretion of Parathormone (parathyroid hormone) causes a decrease in Calcium contents of the blood from the normal 10 mg per 100 ml to 7 mg per 100 ml - signifying LOW LEVELS OF CALCIUM - that leads to excessive contraction of the muscles.
This condition is known as hypoparathyroidism