instruction:
Given a scientific passage and an answer, generate a question for the given answer.
question:
Passage: The cardiovascular system moves nutrients and other substances throughout the body. Answer: cardiovascular system
answer:
Which human body system system moves nutrients and other substances throughout the body?

question:
Passage: Chlamydia is the most common bacterial STI in the U. S. Females are more likely to develop it than males. Symptoms may include burning during urination and a discharge from the vagina or penis. Answer: chlamydia
answer:
What is the most common bacterial sti in the u. s.?

question:
Passage: Birth Prior to birth, the lungs are filled with amniotic fluid, mucus, and surfactant. As the fetus is squeezed through the birth canal, the fetal thoracic cavity is compressed, expelling much of this fluid. Some fluid remains, however, but is rapidly absorbed by the body shortly after birth. The first inhalation occurs within 10 seconds after birth and not only serves as the first inspiration, but also acts to inflate the lungs. Pulmonary surfactant is critical for inflation to occur, as it reduces the surface tension of the alveoli. Preterm birth around 26 weeks frequently results in severe respiratory distress, although with current medical advancements, some babies may survive. Prior to 26 weeks, sufficient pulmonary surfactant is not produced, and the surfaces for gas exchange have not formed adequately; therefore, survival is low. Answer: surfactant
answer:
Prior to birth, the lungs are filled with amniotic fluid, mucus, and what else?