The correct option is B Limnetic zone
The limnetic zone is the well-lit, open surface waters in a lake or pond, away from the shore. The term limentic refers to standing water or swamp or lake. In such a habitat the producers are phytoplanktons, e.g., Diatoms, Desmids, Chlorella, Chlamydomonas, Spirogyra, Oedogonium, Zygnema etc.