Final answer:
A fetus can indeed produce urine and, counterintuitively, the umbilical artery carries deoxygenated blood away from the fetus. The frontal lobes are fully developed only by 25 years old. There is no specific fetal stage where earlobes become firm.
Step-by-step explanation:
The process of fetal development is complex and involves many different stages. True or False: A fetus can produce urine; the answer is True. By weeks 9-12, the fetus circulates amniotic fluid by swallowing it and producing urine. As for the umbilical artery, the statement that it carries oxygenated blood to the fetus is False; the umbilical artery actually carries deoxygenated blood and waste products away from the fetus to the placenta.
Regarding the development of frontal lobes, they are not fully developed at birth; they continue to develop and are fully mature at around 25 years old, making the correct answer d. by 25 years old.
During the fetal development stage, around weeks 16-20, the limb movements become more powerful, and the mother may begin to feel quickening. The bones, including those in the legs, start to ossify, with perhaps the clavicles and leg bones being the first to do so. By week 7, the facial structures, including ears, are more complex. However, the earlobes do not become firm at any specified fetal stage, making the subject question, 'Age earlobes of a fetus become firm', unclear, and presumably, the answer would be False.