What determines whether a solution is acidic or basic?

Idon’t know the answer and i’ve been stuck on it for a while now skskskskks

Which of the following is likely not involved in this example of ecological succession? a) the rotting remains of plants add to the fertility of the soil. b)the soil becomes so fertile that eel grass is replaced by other plant species. c) the roots from plants stabilize the sediment, keeping it in place. d) the concentration of salt becomes so high that all plant life is destroyed.

Plants transfer carbon in the carbon cycle a. through assimilation of carbon from the soil. b. when carbon transpires from their stomatae. c. when they are eaten by animals. d. through fixation of carbon in the soil.plants transfer carbon in the carbon cycle a. through assimilation of carbon from the soil. b. when carbon transpires from their stomatae. c. when they are eaten by animals. d. through fixation of carbon in the soil.