Brutus was putting an aquarium together and asked his little brother to help. His little brother put soda in the tank, not knowing it would be harmful to the fish Brutus and his little brother observe of the fish
struggling to survive. Which of following descriptions would best classify their observation?
a biotic factor limiting a biotic factor
an abiotic factor limiting a biotic factor
a biotic factor limiting an abiotic factor
an abiotic factor limiting an abiotic factor