Best option for floor and ceiling when importing room model into Unreal - new user question

Hello all.
I’m new to Unreal and game design, but I have been using Cinema 4D for 5 years. I have a ‘room’ that I want to import into Unreal from C4D, but I am unsure of how I should bring in the floor and ceiling. I have attached a picture…

A) Using a simple plain as the floor ceiling and combine them.
B) Use a modelled ceiling and floor as a complete and whole model with the quad layout.
C) Use an alternative ceiling and floor as a complete and whole model with quad layout.

Which option would simplified uv layout and lightmapping issues in Unreal.

Many thanks guys!!