A 24-year-old woman presents with a 1-week history of thin, green-yellow vaginal discharge with perivaginal irritation. Physical examination findings include vaginal erythema with petechial hemorrhages on the cervix, numerous white blood cells, and motile organisms on microscopic examination. These findings most likely represent:
A. motile sperm with irritative vaginitis.
B. trichomoniasis.
C. bacterial vaginosis.
D. condyloma acuminatum.

B. trichomoniasis.

Explanation:Trichomonas is a single-celled protozoan parasite best known in medicine because one species causes vaginitis (vaginal inflammation). Infection with trichomonas (trichomoniasis) is the most common curable sexually transmitted disease (STD) in young sexually active women.) in young sexually active women.

Trichomoniasis is a sexually transmitted infection (STI) caused by the motile parasitic protozoan Trichomonas vaginalis.