Answer:
The answer is: Plasterboard, joists and secondary ceilings.
Step-by-step explanation:
The three possible options are:
1.- You can add plasterboard, a sub-ceiling and / or floor as a complement to the floor structure, to hide the wiring.
2.- You can add a floor layer in the form of joists and board using concrete.
3.- The secondary ceilings are used to improve the sound insulation between different parts of a building, but also to hide electricity installations.
The answer is: Plasterboard, joists and secondary ceilings.