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

Ex Input:
Hemodialysis has a patient's blood pass through a length of tubing that travels through an artificial kidney machine.

Ex Output:
Which form of dialysis has a patient's blood pass through a length of tubing that travels through an artificial kidney machine?

Ex Input:
The size and symmetry of a beetle's or an elk's antlers or a grasshopper's song communicate rather clearly their state of health.

Ex Output:
The size and symmetry of a beetle's or an elk's antlers or a grasshopper's song communicate rather clearly their state of what?

Ex Input:
Reacting with metal is one thing that distinguishes acids from bases.

Ex Output:
Reacting with metal is one thing that distinguishes acids from what?