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

[EX Q]: In a carbon triple bond, three pairs of electrons are shared.
[EX A]: In a carbon triple bond, how many pairs of electrons are shared?

[EX Q]: Soft of these best describes the way a feather feels.
[EX A]: Which of these BEST describes the way a feather feels?

[EX Q]: After an infection has been brought under control and most cytotoxic t cells die off, a few remain as memory cells.
[EX A]:
After an infection has been brought under control and most cytotoxic t cells die off, a few remain as what?