Are the hollow structures formed from protein subunits that perform a variety of roles in cell division and in the structure of organelles; are small fibrils that support the plasma membrane and the shape of the cell.

Microtubules, microfilaments

I don't know if you need the first part to it, but it should be:

Microtubules are the hollow structures formed from protein subunits that perform a variety of roles in cell division and in the structure of organelles; microfilaments are small fibrils that support the plasma membrane and the shape of the cell.

prism b but im not for sure

protist eukaryotes that are not plants, animals, or fungi ("misfits")