The correct option is B Spirogyra
Spirogyra is plant-like filamentous green algae (because of the presence of chlorophyll that allows it to make its own food).
Amoeba is a unicellular protozoa.
Euglena is a photosynthetic protist having mixotrophic nutrition.
Chlamydomonas is an unicellular, flagellated green algae.