Final answer:
Hypoparathyroidism, if left untreated, can lead to hypocalcemia, causing severe laryngospasm, which may result in respiratory paralysis and death.
Step-by-step explanation:
Among the conditions listed, hypoparathyroidism can progress to respiratory paralysis and death if left untreated. Hypoparathyroidism leads to low levels of calcium in the blood, a condition known as hypocalcemia. This can cause neuromuscular irritability, leading to spasms (tetany), including laryngospasm, which can impair breathing. Severe cases of laryngospasm can lead to respiratory failure, and without proper treatment, this condition can be fatal.