Step 1: Understand hydrate formation.
Hydrates are salts that contain water molecules as part of their crystalline structure.
Such water molecules are called water of crystallization.
Step 2: Check the given salts.
\(CaCl_2\) forms hydrates such as
\[
CaCl_2\cdot 2H_2O
\]
and
\[
CaCl_2\cdot 6H_2O
\]
So, \(CaCl_2\) forms hydrates.
\(NaCl\) generally does not form a stable hydrate under ordinary conditions.
So, \(NaCl\) is not included.
\(LiCl\) forms hydrates because \(Li^+\) has a small size and high hydration tendency.
So, \(LiCl\) forms hydrates.
\(BaCl_2\) forms hydrates such as
\[
BaCl_2\cdot 2H_2O
\]
So, \(BaCl_2\) forms hydrates.
\(KCl\) generally does not form stable hydrates under ordinary conditions.
So, \(KCl\) is not included.
Step 3: Select the correct set.
The salts forming hydrates are
\[
CaCl_2,\ LiCl,\ BaCl_2
\]
That is,
\[
I,\ III,\ IV
\]
Step 4: Final conclusion.
Therefore,
\[
\boxed{I,\ III,\ IV\ \text{only}}
\]
Hence, the correct option is (4).