Solder is an alloy of A. Tin and lead B. Tin and copper C. Tin, copper and zinc D. Tin, lead and zinc

When tin and lead are mixed together, they form a solid solution. This means that the atoms of tin and lead are randomly distributed throughout the alloy. The properties of the solder depend on the proportions of tin and lead in the alloy.

Solder with a higher percentage of tin is easier to melt and has a lower melting point. This type of solder is often used for electrical connections. Solder with a higher percentage of lead is more durable and has a higher melting point. This type of solder is often used for plumbing and other applications where strength is important.

Solder is a versatile material that is used in a variety of applications. It is a safe and easy-to-use material that can be used to join metal objects together.