Answer:
The littoral zone is found near the sea shore where there is an abundant of sunlight that penetrates to the sediments in the water body and allows the growth of the aquatic plants and animals. This allows the growth of macrophytes that is food for many small aquatic animals.
The benthic zone is located at the lowest level of the water bodies and usually no sunlight reaches to the sediments present there.
So, there is greater biodiversity seen in the littoral zone as compared to that of benthic zone.