Which of the following can be obtained by fractional distillation?

Fractional distillation is a process used to separate a mixture of different substances with different boiling points. The substance with the lowest boiling point will vaporize first and can be collected as a separate fraction. By repeating the process, each component of the mixture can be obtained in a separate fraction. Out of the given options, nitrogen from liquid air can be obtained by fractional distillation because liquid air is a mixture of nitrogen, oxygen, and other gases, and they have different boiling points. By fractional distillation, nitrogen can be separated from the mixture. Sodium chloride from seawater, iodine from a solution of iodine in carbon tetrachloride, and sulfur from a solution of sulfur in carbon disulfide cannot be obtained by fractional distillation because they are not mixtures of substances with different boiling points. Sodium chloride is a compound, and iodine and sulfur are elements. To obtain them, other methods such as precipitation, filtration, or chemical reactions would be necessary.