Verified Answer :

The transfer of electrons is an ionic bond, therefore, we need to determine which substance includes an ionic bond.

CO2, is a covalent bond, which is the sharing of electrons, not transfer.
KBr, is an ionic bond, because (k) loses an electron to bromine. 

So, our final answer is:-   (3) KBr

Answer:

KrS is the answer

Explanation:

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