Which one of the following material is a conductor ?

Which one of the following material is a conductor ?

مندرجہ ذیل میں سے کون سا مواد موصل ہے؟
Explanation

Typically, metals, metal alloys, electrolytes and even some nonmetals, like graphite and liquids, including water, are good electrical conductors.

Pure elemental silver is one of the best electrical conductors.