Which one of the following pairs of organisms and trophic levels is mismatched?

At each trophic level, you will find plants in the position of primary producers.

Algae are simple plants, hence they occupy the position of primary producers in a trophic level.

Phytoplanktons are also microscopic water algae; they produce food through photosynthesis. Therefore, they are also primary producers.

Fungi have a saprotrophic mode of nutrition, which means that they feed on dead and decaying matter. Therefore, they are detritivores.

Bobcats are carnivores and hence, consumers. They are secondary consumers because they do not feed on plants.