In an Aquatic Ecosystem, the Aquatic Plants Are Eaten by Small

In an aquatic ecosystem, the aquatic plants are eaten by small invertebrates that in turn are eaten by crayfish, the crayfish are eaten by fish, and the fish are eaten by ducks. Based on this, which of the following is incorrectly matched?

A) aquatic plant - producer
B) crayfish - secondary consumer
C) duck - 4^th trophic level
D) fish - tertiary consumer
E) small invertebrates - 2^nd trophic level