On exposure to air, Some articles made of silver, copper, and iron get a colored coating over them. Identify the color along with the chemical name of the substance of the coating in each case.

Silver, iron, and copper react with oxygen in the atmosphere or with sulfur dioxide to form oxides. These oxides of each metal have their characteristic color forming a colored coating on the article.  

The colored coating formed is the result of metal corrosion in the presence of oxygen or sulfur dioxide or other compounds. The coating is generally a thin layer. Also called turbidity. 

Let's see what it looks like in each case.

1. Silver-black coating (Silver sulfide)
2. Copper-green coating (copper oxide)
3. Iron-reddish brown (ferric oxide)

Hence, the correct option is (D).