A 12 year old female went to her doctor for her yearly back-to-school check-up. She was in good health and was asymptomatic at the time of the examination. Due to the increased incidence of parasites in the area, the doctor ordered a stool for parasite examination as part of the routine physical testing. Multiple suspicious forms, measuring approximately 9 µm each were seen. Which of the following is most likely the identification of these forms?

Please select the single best answer