The cell is a network of protein filatments and tubules that give support to the cell and may move organelles around inside the cell.

cytoskeleton

Explanation: the cytoskeleton of a cell is a complex network of protein fibres.it is found within the cell cytoplasm and regarded as the skeleton of the cell.this is because it is responsible for maintaining the shape of the cell , movement of the cell, movement of organelles within the cell and aids movement in Unicellular organisms.

The cytoskeleton is composed of the microfilaments, microtubules and the intermediate filaments.

The microfilaments are thin and flexible filaments composed primarily of actin.it is thin and flexible.the microfilaments allows cell motility,determines the shape of the cell .

The microtubules are hollow tubes composed of protein protofilaments.they allow for movement of water within the cell and it is the backbone of cilia and flagella .they are also involved in the separation of chromosomes during cell division.

The intermediate filaments gives cell tensile strength.

the answer is "a.) well–developed vascular system."

explanation: