Here is what I found, its quite interesting, I hope it helps..
https://www.fbi.gov/services/laboratory/biometric-analysis/codis/codis-and-ndis-fact-sheet
The food sources available for a particular species in an ecosystem. Also space where they can live and reproduce, but food is the main factor.
I think the correct answer from the choices listed above is option A. For metamorphism to occur, the parent rock must be in solid form. Metamorphism is the alteration of the structure of a rock by factors like heat and temperature so it must be the material should be in solid form.
I believe the answer you're looking for is fertilization. :D
