Which of the following cell types is known for having a rigid cell wall?

Plant cells and prokaryotic cells both possess rigid cell walls, which serve structural and protective functions.

In plant cells, the cell wall is primarily composed of cellulose, providing rigidity, support, and protection against mechanical stress and pathogens. The presence of this rigid structure allows plants to maintain their shape and withstand osmotic pressure, enabling them to grow tall and remain upright.

Prokaryotic cells, such as bacteria, also have a rigid cell wall, which is typically made of peptidoglycan in bacteria. This peptidoglycan layer supports the cell and maintains its overall shape, playing a crucial role in protecting the bacteria from external environmental factors and contributing to the integrity of the cell during cell division.

In contrast, animal cells do not have a cell wall; instead, they are surrounded only by a flexible cell membrane, which allows for a variety of shapes and sizes. Therefore, the combination of plant and prokaryotic cells having rigid cell walls makes the choice that both of these types are known for this characteristic the correct one.