Final answer:
Water conducts electricity when it contains dissolved ions because these ions move freely and carry charge, thus creating an electric current. Nonmetals can form ions, but the key is free ion presence, not the specific type of atom. Pure water or molecular compounds without ions do not conduct electricity.
Step-by-step explanation:
To understand why water can conduct electricity when it contains dissolved ions, we need to recognize the properties of substances known as electrolytes. Electrolytes are materials that dissolve in water to form a solution that conducts electric current because of the presence of freely mobile, charged species, which are ions. In the context of the student's options, only option A) which refers to small amounts of dissolved nonmetals, is not a correct description of what allows water to conduct electricity. While nonmetals can form ions, it is specifically the presence of free ions, whether from metals or nonmetals, that matters. Dissolved ions are key in this process because when they are in solution, they can move freely and carry an electric charge, whereas in a solid state, such as solid sodium chloride, ions are fixed in place and cannot carry an electric current. When an ionic substance is dissolved in water, the ions become separated and can move independently, allowing the solution to conduct electricity. This is contrasted with pure water or non-ionizing molecular compounds, which do not provide the necessary charged particles for electrical conduction.