Each of the following options contains a set of four molecules. Identify the option(s) where all four molecules possess a permanent dipole moment at room temperature.

Correct option is D. SO2, C6H5Cl, H2Se, BrF. All molecules in option D possess a permanent dipole moment at room temperature due to their asymmetrical molecular geometries and the presence of polar bonds. Let's examine each molecule:

• SO2 (Sulfur dioxide): The bent molecular geometry results in a net dipole moment.
• C6H5Cl (Chlorobenzene): The electronegativity difference between chlorine and carbon creates a polar C-Cl bond, leading to a permanent dipole moment.
• H2Se (Hydrogen selenide): Similar to water, the bent geometry and the electronegativity difference between selenium and hydrogen result in a net dipole moment.
• BrF (Bromine fluoride): The electronegativity difference between bromine and fluorine creates a polar bond, resulting in a permanent dipole moment.

The other options contain molecules with symmetrical geometries (like BF3, CO2, BCl3, and SF6) or molecules where the polar bonds cancel each other out, resulting in a zero net dipole moment.