The members of algae found in the littoral zone is
A. Volvox
B. Spirogyra
C. Ectocarpus
D. Ulothrix

Hint: The littoral zone is termed as the kind of ecosystem usually observed by the presence of abundant water motion, nutrients, dissolved oxygen and alternating intervals of submergence and exposure. Brown algae are also known to be found in this zone.

Complete answer: The littoral zone is termed as a near-shore area of lakes, and it is an essential interface between the pelagic zone and the terrestrial ecosystem. The physical structure, the local nutrient processing, and the habitats of the littoral zone are controlled by the basin morphometry of lakes, surrounding topography and geology, and the wind patterns. The littoral zone gives a response to conditions of nature and humans in the terrestrial ecosystem as an interface and likewise interacts with the profundal and pelagic zones.
a) Volvox: it is a kind of filamentous algae usually observed to occur in ponds, lakes, rivers and they are found in limnetic zones.
b) Spirogyra: They are usually green algae which are branched and filamentous in nature. They are found in freshwater bodies, therefore, they are not present in the littoral zone.
c) Ectocarpus: They are cosmopolitan in nature, which means that they can be found to exist everywhere in nature. They are present in stones or rocks, therefore, they are known to be observed in the littoral zone.
d) Ulothrix: They are green algae, therefore, they are known to occur in freshwater.
Hence, the correct answer is option C.

Note: The types of living things known to exist in the littoral zone depend to an extent on the degree of the zone's exposure to wave action. Littoral zones are of three types; supralittoral zone, eulittoral zone and sublittoral zone.