Which of the following could NOT result from monozygotic twinning?

Which of the following clinical symptoms would be most common in a patient with these sonographic findings?  

Which of the following would be described as the coverings of the brain and spinal cord?

This transverse transabdominal image of the gravid pelvis reveals an adnexal mass. The patient presented to the emergency room with a history of vaginal bleeding, hypertension, and excessive vomiting. Her human chorionic gonadotropin was markedly elevated. Within the uterus, a large complex mass with cystic components was identified. What is the most likely diagnosis?

A patient presents to the ultrasound department with a history of hydronephrosis. Which of the following would be the least likely pelvic cause of this abnormality?

Which of the following anomalies can be detected in the first trimester with endovaginal scanning?

You are performing a pelvic sonogram on a 65-year-old patient for pelvic pain. The endometrial thickness appears symmetric, echogenic, and measures 3 mm. Which of the following statements is true?

The arrows in this image of the fetal abdomen are indicating the presence of:

During the follicular phase of the ovarian cycle, what hormone is produced by the anterior pituitary gland?

This image is demonstrating sonographic features of: