Final answer:
SO2, sulfur dioxide, is the covalent compound among the given options because it is formed by the sharing of electrons between nonmetal atoms, sulfur, and oxygen. So option (d) is correct.
Step-by-step explanation:
From the set of compounds given, SO2 (sulfur dioxide) is the covalent compound. In a covalent compound, atoms are held together by shared pairs of electrons. Sulfur (S) and oxygen (O) are both nonmetals, and when nonmetals combine, they tend to share electrons, forming a covalent bond. In contrast, ZnS (zinc sulfide) and Fe2O3 (iron (III) oxide) are ionic compounds, as they are composed of metals (Zn, Fe) and nonmetals (S, O), where the metal atoms give up electrons to the nonmetal atoms, forming positively and negatively charged ions that are held together by ionic bonds.
Predicting whether a compound is ionic or covalent can often be done by looking at the types of atoms involved and their position in the periodic table. Nonmetal atoms bonded together generally form covalent bonds, while a metal bonded to a nonmetal typically forms an ionic bond.