You are presented with the question "Space explorers require preserved foods for" and the following answer choices: 
- ground training
 - nutrients
 - Dehydration
 - survival
 - long flights
 - short flights
 - Special disposal
 - day trips

Now knowing that astronauts require preserved food for extended flights and an astronaut is a scientist who is a space explorer, choose the best answer.


 

     long flights    