Which of the following is the best electrical conductor?

The best electrical conductor is silver (option D). Silver has the highest electrical conductivity of all metals, surpassing even copper, which is also an excellent conductor. The high conductivity of silver is due to its atomic structure, which allows electrons to move more freely than in other materials. This property makes silver ideal for applications requiring maximum electrical efficiency, such as high-quality audio cables, specialized electrical contacts, and certain types of electronic components. However, the high cost of silver limits its widespread use in everyday electrical wiring and components, where copper is more commonly used due to its excellent conductivity combined with lower cost. Aluminum, while also a good conductor and lighter than copper, is less conductive than both silver and copper. Iron, although useful for many applications, is not as efficient a conductor as silver, copper, or aluminum.