The correct option is B Bacillariophyceae
Bacillariophyceae is a class of yellow-green algae (division Chrysophyta) comprising the diatoms.Diatoms may be either unicellular or colonial. The diatoms are important components of planktonic and benthic communities in a wide range of marine and fresh water habitats. The cells are normally protected by a wall called a frustule, composed of silica (SiO2) and surrounded by mucilage. The frustula is composed by two valves epitheca or epivalve (larger) and hypotheca or hypovalve (smaller). The loops inserted between the valves are the Girdle bands or cingulum.