Your answer is (B). Hope this helps =3
If the question is multiple choice, please include the options in the questions to make things easier.
The answer is main clause
Answer:
After the Cuban revolution led by Fidel Castro in 1959, a Cuban exodus began as the new government allied itself with the Soviet Union and began to introduce communism. From 1960 to 1979, tens of thousands of Cubans left Cuba, with the vast majority coming from Cuba's educated, landowning upper class.
Explanation: