An example of deliquescent salt is-

The correct option is A

CaCl₂

Deliquescent salts :

Deliquescent salts are those that absorb moisture from the air and then dissolve themselves in the water absorbed to form a solution.

Explanation of the correct option:

Calcium Chloride (CaCl₂₎ is one example of deliquescent salt.

Hence, the correct option is option(A) CaCl₂.

Explanation of the incorrect options:

Option B :

Calcium Sulphate (CaSO₄) is a type of efflorescent salt that give up its water molecules when exposed to air.

Option C :

Copper sulphate (CuSO₄) is a type of hygroscopic salt that absorbs water from its surroundings.

Option D :

Sodium Chloride (NaCl) is also a type of hygroscopic salt that absorbs water from its surroundings.

An example of deliquescent salt is CaCl_2.