Correct option is C
✅ (c) Yellow vein mosaic: • Most severe and economically damaging disease in Okra. • Caused by Yellow vein mosaic virus, transmitted by whiteflies. • Leads to chlorosis and reduced fruit yield. • Highly prevalent in Okra-growing areas. ❌ (a) Root rot: • Important but not as destructive. ❌ (b) Powdery mildew: • Occasional, less severe. ❌ (d) Downey mildew: • Rarely affects Okra seriously.