Blossom end rot of tomato is caused due to deficiency of

Answer: Option A

Blossom end rot of tomato is caused due to deficiency of Calcium.
Blossom-end rot is a physiological disease caused by a localized deficiency of calcium in the fruit. Calcium is a nutrient that is required in relatively large quantities by rapidly growing fruit, especially by those cells at the blossom end of the young fruit.