Explanation:
Where is the picture? You have not attached it in your question
D. All of a sudden could be changed to suddenly
The answer should be an object of a verb. The bold words are neither a proposition(which is a word that expresses a relation to another word, like "after" or "next to") or the subject. The subject in this case would be the city of Washington.
The correct answer is b. Illegal immigration causes additonal obstacles for the immigrant: the problems that her father has with work and also her mother who cannon work herself as she hasn't obtained citizenship.
