Question

the flexibility of the plasma membrane is caused by the ability of the phospholipids, that compose the membrane, to?. move become charged stay in one place dissolve

Explanation:

The plasma membrane's flexibility is due to the fluid - mosaic model. Phospholipids in the membrane can move laterally (side - to - side) within the bilayer. This movement allows the membrane to change shape, which is the basis of its flexibility. Phospholipids becoming charged (\(e.g.\), in response to certain stimuli) is not the main cause of membrane flexibility. If phospholipids stayed in one place, the membrane would be rigid. Phospholipids do not dissolve in the aqueous environment of the cell (they form a bilayer due to their amphipathic nature - hydrophilic heads and hydrophobic tails), so dissolution is not the reason for flexibility.

Answer:

move