*Q:06 Correct Answer* ✅ (3) A is true but R is false > *Explanation:* Black rust of wheat is indeed a serious disease caused by the fungus Puccinia graminis. However, aflatoxin is not produced by a bacterium — it is a toxin produced by the fungus Aspergillus flavus, commonly found contaminating groundnuts and other stored grains under moist conditions.