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

All life is built around the element carbon.
What element is all life built around?

Lead sulfate is the white solid that forms on corroded battery terminals.
What is the white solid that forms on corroded battery terminals?

In aquatic communities, the main producers are photosynthetic protists and prokaryotes.
In aquatic communities, the main producers are photosynthetic protists and what?