Given scientific fact as input, generate the question from this fact such that it can be answered from the input.

[EX Q]: Interstitial fluid are all hormones secreted into before entering the circulatory system.
[EX A]: Where are all hormones secreted into before entering the circulatory system?

[EX Q]: A fewer predators is most likely to cause the number of rabbits living in an area to increase.
[EX A]: Which factor is most likely to cause the number of rabbits living in an area to increase?

[EX Q]: Preventive vaccinations can you prevent diseases such as whooping cough and flu.
[EX A]:
How can you prevent diseases such as whooping cough and flu?