Khaira disease in rice is caused due to deficiency of

Answer: Option C

Khaira disease in rice is caused due to deficiency of Zinc.
Khaira disease Of Rice is a micro-nutritional (Zn) deficiency characterized by the presence of dusty brown patches on leaves which ultimately undergo necrosis. This is one of the most common diseases in rice.
Treatment of rice seed with 0.4% ZnSO₄ before sowing or of seedlings before transplanting gives control. Spraying with 0.4% ZnSO₄ + 2% urea on the appearance of the symptoms is useful.