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

Protons and neutrons are made of quarks, which are fundamental particles of matter.
A fundamental particle of matter, protons and neutrons are made of these?

Clear mucus is secreted before ejaculation to neutralize acidic urine remaining in the urethra.
What is secreted before ejaculation to neutralize acidic urine remaining in the urethra?

Water molds mostly live in water or moist soil.
Water molds mostly live in water or moist?