The correct option is B slimy mass of multinucleate protoplasm having pseudopodia-like structures for engulfing food, reproduction through fragmentation and spore formation
Myxomycetes includes slime moulds that belong to Kingdom Protista. These unicellular organisms aggregate together and the cell membranes disappear. This results in a multinucleate mass of protoplasm called plasmodium stage. They have pseudopodia-like structures for engulfing food. They perform vegetative reproduction by fragmentation. Under unfavourable conditions, they reproduce by forming spores.