I think it is C. However, it should just be rock and water/ice.
I'm sorry i do not know the answer, but in the picture you took i noticed how it said hint try clicking on that and I also noticed it said chapter 2 at the top of the page if that is a reading source that has information i would read through that or put a link to that so we can read it and see if it helps us get the most accurate answer.
Due to loose environmental and worker safety laws in factories, Death Rates along the Texas-Mexico border are some of the world's highest
what make people cringe is that 85 % of the bodies that found dead in Texas-Mexico border are the workers that came from Mexico, not Texas.
hope this helps
