Answer:
D. Emigration
Step-by-step explanation:
The answer is D. because the actual definition for emigration is: "The act of leaving one's own country to settle permanently in another; moving abroad." The definitions between immigration and emigration are very similar but the actual definition for immigration is: "The action of coming to live permanently in a foreign country." so I would stick with D.
sorry if I'm not right I hope you do good!