Disease due to deficiency of Vitamin D is :

Osteomalacia

The correct answer is Option (4) – Osteomalacia

The disease due to a deficiency of Vitamin D is Osteomalacia.

Explanation:

• Osteomalacia is a condition characterized by softening of the bones, often leading to pain and weakness.
• Vitamin D is essential for the absorption of calcium and phosphorus in the intestines. A deficiency of Vitamin D can result in impaired mineralization of bone matrix, leading to weakened and softened bones.
• Night blindness is associated with a deficiency of Vitamin A.
• Scurvy is caused by a deficiency of Vitamin C.
• COVID-19 is a respiratory illness caused by the SARS-CoV-2 virus and is not related to a deficiency of Vitamin D.

In summary, Osteomalacia is the disease associated with a deficiency of Vitamin D.