Answer:
C.The impact would be negative because it would increase competition with native clams and reduce the stability of the ecosystem.
Step-by-step explanation:
Since, It states that:
Tank 1: Tank 2:
Fish Fish
crayfish crayfish
Asian clam
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Thus, since they both eat Asian clam which means competition as well as it would be negative. Therefore, that left us with [C] .
Hence, Answer = [C]
~Lenvy~