If we cannot place all the luggage in the boot, can we do so inside the passenger compartment?

If we cannot place all the luggage in the boot, can we do so inside the passenger compartment?
A)Yes, but bearing in mind that it does not bother the passengers, reduce freedom of movement or decrease the driver's field of vision, and that it is well secured.Correct
B)Yes, only if they are small, lightweight boxes and there are no occupants in the rear seat.
C)No, luggage may only be placed in the boot, the roof rack or in a small trailer.
If the load does not fit in the boot, it may be placed inside the vehicle without obstructing the driver's vision or movements. We must also bear in mind that in the event of a collision against a rigid object, the vehicle will stop abruptly, but the load being transported, if not properly secured, will continue moving at the same speed the vehicle was travelling at before the impact, with the negative consequences that this may cause to the vehicle's occupants.