Water will have higher specific heat compared to metals Copper and Silver. Water has a specific heat of 1 cal/gm/K or 4.18 J/gm/K.
As copper, Silver are metals and conduct heat and electricity very well, they generally take very little heat to get hotter by 1 deg. So specific heat will be low for metals or good conductors.
Is the 4 th element Hydrogen? Then it has the highest specific heat..
For diatomic gases, the Cv = heat capacity = 5/2 * R which is [ ΔQ /ΔT ]_V.
so Cv = 2.5 * 8.314 J/K/mol = 2.5 * 8.314 /2 J/K/gm
For the constant pressure: Cp = 7/2 * R
so Cp = 3.5 * 8.314 / 2 J/K/gram