Answer:proton
For our purposes at this point in the text, we can define an acid. as a substance with at least one hydrogen atom that can dissociate to form an anion and an H + ion (a proton) in aqueous solution, thereby forming an acidic solution.
Explanation: hope it helps!
Plants absorb me from the soil through assimilation, I am eaten by animals the animals and plants die and decompose where I am released back into the soil, weathering and erosion cause me to release out of rocks, I then find my way into the ocean being carried by water, I then return to the soil through the water.
Occluded front I think this answer is correct
D. A struggle for existence is apparent.
If a struggle for existence is apparent, natural selection occurs because all of the weak/unfit/unadapted ones die.