I’m pretty sure it’s the second one
C
Because if you look at the last stage the crust of the earth is a solid so it has to be c
They are reactants because they are present before the reaction
Explanation:
Due to lack of O2, the lungs will start breathing anaerobically i.e; without oxygen this may lead to cramps
Because people throws trash into rivers and stuff and they flow down into the ocean and makes it unclean
