Answer:
(d) Cell wall
Explanation:
The cell wall is a structure located on the outside of the cell membrane in the cells of plants, bacteria, fungi, and algae. It is a resistant, tough and flexible layer, which has the vital function of supporting the osmotic pressure inside the cell, preventing the cell from lysis when water enters. Besides, it has the function of giving rigidity, support and defining the shape of the cell.
Flatworm<span>, also called platyhelminth, any of the phylum Platyhelminthes, a group of soft-bodied, usually much flattened invertebrates. A number of </span>flatworm<span> species are free-living, but about 80 percent of all </span>flatworms are<span> parasitic—i.e., living on or in another organism and securing nourishment from it.</span>
