The correct option is B slime moulds
The vegetative stage of slime molds is essentially a multinucleate mass of protoplasm (called a plasmodium) composed of numerous diploid nuclei. Depending on the species, the plasmodium may be only a few millimeters in diameter to large pizza-sized slime molds over 12 inches (30 cm) across. The plasmodium moves like a giant amoeba, flowing over the surface as it ingests organic matter, such as dead leaves and wood. It may be be brightly colored, such as the yellow Physarum polycephalum commonly studied in general botany laboratories.