The principal ores of silver are argentite,horn silver and pyrargyrite. Their formulas respectively are:

• A
  $Ag_2S, AgCl$ and $AgSbS_2$
• B
  $AgCl, AgSbS_2$ and $Ag_2S$
• C
  $AgSbS_2, Ag_2S$ and $AgCl$
• D
  $AgCl, Ag_2S$ and $AgSbS_2$