Help plz In a meadow where earthworms live in the soil, the pH gradually decreases from the optimum range into the zone of stress. What is the MOST LIKELY effect on the earthworm population?

A. The size of the earthworm population increases, but otherwise the population is unchanged.
B. The size of the earthworm population decreases, but otherwise the population is unchanged.
C. Earthworms that tolerate high pH become more common in the population.