Answer:
The correct option is They are made of cells
Explanation:
Cell is the structural and functional unit of life. Although, the three specimen given are of different "classes" but they are all of living origin. And all living things are made up of cells. For instance, Elodea is an aquatic plant (popularly called waterweed) is made up of plant cells. While Muscle is a tissue found in many animals and is made up of cells (muscle cells/myocytes); since cells generally join together to form tissues. Fungus is a eukaryotic organism and hence is also made of cells.