Having two flagella, cellulosic cell plates and show bio- luminescence. These are feature of a. Gelidium b. Pythium c. Gonyaulux d. Slime moulds
Option C Dinoflagellates are basically unicellular motile and biflagellate, golden brown, photosynthetic protists. The predominant colour is golden brown but yellow, green, brown and even blue forms also occur due to change in the proportion of various pigments. Cells are generally covered by a rigid coat known as the theca or lorica of articulated and sculptured plates of cellulose. The two flagella are different (heterokont), one transverse flagellum and other longitudinal flagella. The nucleus is large in size and has been named mesokaryon. Plastids or chromatophores have chlorophyll a and chlorophyll c. Some dinoflagellates like Gymnodinium and Gonyaulax grow in large number in the sea and make the water look red and cause the so-called "red tide". Some marine dinoflagellates show bioluminescence. e.g. Noctiluca.