When they are capable of interbreeding to produce a viable/ fertile off-springs.
That would be erosion. I know this because i spent years studying rocks and had straight passed all of it. Hope this helps. ;)
Answer: A
Explanation:
The three reactants used in photosynthesis are water (H2O) carbon dioxide (CO2), and light (sunlight energy). These reactants are used to produce glucose/food for plants and oxygen that is later released.
