Answer:
a) Li and Cl, because one is a metal and the other is a nonmetal
Explanation:
An ionic compound is usually formed between a metal and a non metal. Recall that an ionic bonds involve the transfer of electrons from the metal to the non-metal.
in an ionic bond, there must be a significant difference between the electro negativities of the bonding atoms for electron transfer to occur. This is why the ionic bond only occurs between a metal and a non-metal.