The correct answer is D. All the above.
Solder is an alloy that melts at a temperature below 450°C. It is used to join two pieces of metal together by melting the solder and flowing it into the joint. The solder then cools and hardens, forming a strong bond between the two pieces of metal.
Brazing is a similar process, but it uses a filler metal that melts at a higher temperature than solder. Brazing filler metals typically melt between 600°C and 1100°C. The filler metal is melted and flowed into the joint between the two pieces of metal, and then it cools and hardens to form a strong bond.
Brazing joints are typically stronger than solder joints. This is because the brazing filler metal has a higher melting point than solder, and it is able to flow into the joint more easily. This results in a stronger bond between the two pieces of metal.
In addition, brazing filler metals are often made of materials that are more corrosion-resistant than solder. This means that brazed joints are less likely to corrode over time.
Overall, brazing is a more versatile and durable process than soldering. It is often used in applications where strength and corrosion resistance are important.