Q: Fact 1: Astronauts require preserved food for extended flights. Fact 2: For example, food contains Calories, units of energy content. Given the two facts above, what do astronauts require for long flights?

Options: 1. problems. 2. nutrients. 3. glycogen. 4. danger. 5. energy. 6. sugar. 7. hydration. 8. trouble.
The answer is:
5.