Concept:Using poison in water bodies kills fish indiscriminately and damages aquatic life, so discouraging it helps protect fish populations.Explanation:Poisoning a large water body kills many fish at once, including young and breeding fish.This can drastically reduce the number of fish available for reproduction.It also contaminates the water and harms other aquatic organisms.Therefore, avoiding poison as a fishing method supports the survival and renewal of fish species.Answer:B. conserving the fish species.