Final answer:
The statement is true. Brazing rod or filler metal is available in a variety of brazing alloys such as silver, phosphorus, and copper alloys. Therefore option a is correct.
Step-by-step explanation:
The statement 'Brazing rod or filler metal is available in a variety of brazing alloys such as silver, phosphorus, and copper alloys' is true. Brazing is a metal-joining process wherein a filler metal is heated above melting point and distributed between two or more close-fitting parts by capillary action. The most common types of brazing alloys are indeed those that include silver, phosphorus, and copper.
Alloys are mixtures of materials that include at least one metal. Brass, an alloy of copper and zinc; bronze, an alloy of copper and tin; and steel, often an alloy of iron and carbon; are widely used in various applications due to their enhanced properties. Alloys like bronze were essential in history for making weapons, while alloys like brass are valued for their acoustic properties in musical instruments.
The subjects of copper, brass, and bronze are especially pertinent to your question, as they represent common base metals and alloys relevant to brazing processes. Brazing rods or filler metals must match the mechanical properties and melting temperatures suitable for the materials being joined.