Final answer:
The ion attracted to a magnetic field is Fe³⁺ (D) because it has unpaired electrons in its d-orbital, which makes it paramagnetic.
Step-by-step explanation:
The ion that will be attracted to a magnetic field is the one with unpaired electrons in its electron configuration. These unpaired electrons cause the ion to have magnetic moments that interact with the magnetic field.
Both sodium (Na+) and potassium (K+) ions have their outermost electron shells fully paired and are therefore not magnetic. The chloride ion (Cl−) also has a complete set of paired electrons after gaining an electron to achieve a noble gas configuration.
In contrast, the iron(III) ion (Fe3+) has unpaired electrons in its d-orbital, which makes it paramagnetic and attracted to a magnetic field. Therefore, the correct answer is D) Fe3+.