Which extinguishing agent must NEVER be used on fires involving Class 4.3 Substances Which in Contact with Water Emit Flammable Gases (e.g. Metallic Sodium UN 1428, Calcium Carbide UN 1402)?

1. Water, aqueous foam, or wet chemical agents (must use dry sand, Class D dry powder, or dry graphite)
2. Dry sand
3. Class D specialized dry powder
4. Dry sodium chloride / graphite powder