Maximum exposed area of fire-rated glass is 2 m², but the window is 5 m².

Fire-rated glass must be installed within manufacturer’s tested maximum exposed area. Oversized panes risk failure under fire conditions. If the window exceeds 2 m², the correct approach is to subdivide it into smaller sections, each ≤2 m², using approved fire-rated frames.

Options B and C (silicone or aluminum splits) are not certified fire-rated framing methods. Option A is unsafe because normal glass provides no fire protection.

Therefore, option D ensures compliance and safety.