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

[EX Q]: Some gametophytes develop underground and form mycorrhizal associations with fungi.
[EX A]: Some gametophytes develop underground and form mycorrhizal associations with what?

[EX Q]: For to synthesize glycogen purpose does liver use the excess carbohydrate.
[EX A]: For what purpose does liver use the excess carbohydrate?

[EX Q]: The 'counting' instrument geiger counter is used to measure radioactivity.
[EX A]:
What 'counting' instrument is used to measure radioactivity?