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

Seismic waves prove the inner core it is solid.
What do seismic waves prove about the inner core?

A pregnant woman should avoid toxic substances while pregnant.
What should a pregnant woman avoid while pregnant?

Comprised mainly of collagen and associated with long bones and the skull, hyaline is the most widespread type of collagen.
Comprised mainly of collagen and associated with long bones and the skull, hyaline is the most widespread type of what?