Answer:
Only II) is correct
Explanation:
I) The red color of the rubies is a physical property of its own structure (wich contains chromium ions)
II)Objects made of silver become tarnished not by a physical property, but as the result of a chemical reaction on the surface of the object made of silver in combination with the sulfur in the air
[tex]2Ag_{(s)}+S\rightarrow Ag_{2}S[/tex]
This changes the color of the object to black, (similar to the iron oxidation)
iii)Boiling is a physical change where a liquid substance absorbs heat in some way (e.g. a flame) and becomes a gas
