Answer:
D. Warmed air sinks is not a normal convection cycle outcome
Explanation:
Warm air is buoyant and rises. Cold air is dense and sinks.
Think of fog in the air. Fog forms in low/cool areas, as the sun comes out and warms up the atmosphere the upper atmosphere, heat flows to cold so upper atmosphere air displaces the fog.
Space heating, the steam or hot water radiators are placed along the floor typically causing convection of warm air to rise up over windows and cold walls, breaking up cold air drafts.