Which of the following is an example of a double displacement reaction?

The reaction between sodium sulfate and barium chloride to form barium sulfate and sodium chloride is an example of a double displacement reaction. This reaction involves the mutual exchange of ions between the two reacting compounds, where the sodium ions (Na+) pair with chloride ions (Cl-) and barium ions (Ba2+) pair with sulfate ions (SO4^2-). It is characterized by the formation of an insoluble white precipitate of barium sulfate, which settles at the bottom of the test tube during the process.