All are important causes of UTI except-

Ans. is 'd' i.e.. Streptococcus viridanso The dominant etiologic agents, accounting for more than 85% of cases of urinary tract infection, are the gram-negative bacilli that are normal inhabitants of intestinal tract,o By far the most common is Escherichia coli, followed by proteus, klebsiella, and Enterobacter.o In most patients with urinary tract infection, the infecting organisms are derived from the patient's own fecal flora. This is thus a form of endogenous infection.