Final answer:
H₂O (water) is the compound among the given options that would form a covalent bond, as its hydrogen and oxygen atoms share electrons to achieve stable electron configurations.
Step-by-step explanation:
The compound that would make a covalent bond among the given options is H₂O (Water). Covalent bonds are formed when two atoms share electrons to obtain a full outer shell of electrons. In the case of H₂O, each hydrogen atom shares one of its electrons with the oxygen atom, and the oxygen atom shares one of its electrons with each hydrogen atom, creating a stable electron configuration for all involved atoms. Other options such as NaCl, CuCl₂, and Cu-Zn are not covalent compounds. NaCl is an example of ionic bonding, where electrons are transferred from sodium to chlorine, creating ions that are held together by electrostatic forces. CuCl₂ consists of ionic bonds between copper and chlorine, and Cu-Zn is a metallic alloy, not a compound, which involves metallic bonding.