Social & Preventive Medicine Communicable diseases bee6781c Commonest trophozite infection by sexual intercourse - A Entamoeba histolytica B Trichomonas vaginalis C Trepanoma palidium D Giabrdia intestinales High-Yield Explanation Trichomoniasis has an estimated annual incidence of 173 million cases(Ref.PARK'S TEXTBOOK OF PREVENTIVE AND SOCIAL MEDICINE 21st Edition page no.304)