In which of the following algae, motile colonies are found?

Step-by-step solution

Volvox belongs to the Chlorophyceae family. They are mostly found in freshwater bodies. They form beautiful green coloured phytoplanktons on the surface of the water body. In Volvox , motile colonies are found that possess two whip-like flagella. In their body, there is a small red eyespot present that helps them to swim towards the light.