Given a statement, generate a question such that the answer is contained in that statement.

Ex Input:
a sifter is used for separating combined constituents

Ex Output:
What is used for separating combined constituents?


Ex Input:
h2o is essential for all plants on Earth

Ex Output:
What is essential for all plants on Earth?


Ex Input:
ink is used for hiding from sharks by squids

Ex Output:

What is used for hiding from sharks by squids?