Reactive ahritis is usually caused by

Ans. is 'a' i.e., Shigella Flexneri Organisms that have been associated with ReiterAhritis include the following: C trachomatis (L2b serotype) Ureaplasma urealyticum Neisseria gonorrhoeae Shigella flexneri Salmonella enterica serovars Typhimurium Mycoplasma pneumoniae Mycobacterium tuberculosis Yersinia enterocolitica and pseudotuberculosis Campylobacter jejuni Clostridium difficile Beta-hemolytic (example, group A) and viridans streptococci