Which of the following statements regarding medieval astronomers can be inferred from the passage? A. They were skeptical of the idea that certain astronomical configurations could produce high flood tides. B. They had an understanding of the effect of the Sun and Moon on ocean tides. C. They could calculate lunar positions with some accuracy, but not the positions of the Sun and Earth. D. Although they were highly skilled in celestial calculations, they were unlikely to apply this knowledge to predictions of events on Earth. E. They possessed the mathematical skills for performing only the simplest of astronomical calculations.