Who of the Following Would Most Likely Be Called a "Refugee

Who of the following would most likely be called a "refugee" rather than an "immigrant"?

A) Carlos, who came to the U.S. to escape political persecution.
B) Katarzina, who came to the U.S. to earn money to send back to her family.
C) Salma, who secretly crossed the U.S. border with friends and family.
D) Kim, who married a U.S. marine and came back to the United States with him.