Engineered oak flooring. Double-layer board - the first layer of moisture-resistant plywood FSF 10mm, the second layer of oak 4 mm, tenon / groove on 4 sides.
Once fitted an engineered floor is indistinguishable from a solid wood floor, but because it is multilayered the engineered wood is more stable and will withstand changes in humidity far more successfully. In fact, it is so stable most engineered oak floors can be installed over underfloor heating.
Depending on the thickness of the top layer, engineered wood may also be sanded down and refinished just like a solid wood floor. And those with a 6mm top layer may be re-sanded equally as often. Sanding down will, of course, affect any surface finishes.