Step 1: Understanding surface treatment.
Surface treatment involves modifying the surface of a material to achieve improved appearance, corrosion resistance, wear resistance, or other properties.
Step 2: Analyze the options.
Soldering and riveting are joining processes, not surface treatments. Extrusion is a bulk deformation process used to shape metals. Thermoplating, on the other hand, is a surface treatment method in which a metal is coated with another by applying heat.
Step 3: Conclusion.
Among the options, thermoplating is specifically used for surface treatment of metals.
Final Answer: Thermoplating
Match the buildings in Group I with their corresponding structural systems in Group II. 
