What causes the disease known as black arm of cotton?

-✅Explanation: Black arm of cotton is a bacterial disease caused by Xanthomonas malvacearum (also sometimes known as Xanthomonas axonopodis pv. malvacearum). This bacterium causes angular lesions on leaves, stems, and bolls, impacting plant health and fiber quality.
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📌Other Options Explanations:
-Phytophthora infestans: Causes late blight of potato.
-Pseudomonas solanacearum: Causes bacterial wilt in various plants.
-Colletotrichum spp.: Causes anthracnose diseases.