The benthic organisms are known to get benefited from the presence of the zebra mussels.
Hence, the correct answer is benefit from the presence of zebra mussels.
The zebra mussels gets colonised and increase the complexity of the substartes. the faeces and the pseudofaeces released by the zebra mussels act as a food resource for many macroinvertebrates, including the benthic organism.
The zebra mussels feeds on phytoplanktons and increase the water clarity, it also changes the nutrient content, which provide an additional advantage for the survival of the benthic organisms.