Here are the answers to your questions:
Question 1
A) Which description defines a dependent clause?
Answer: It contains a subject and a verb but cannot stand alone.
Question 2
A) Which characteristic describes an independent clause?
Answer: It includes a subject and a verb and can stand alone.
Question 3
A) How is a phrase different from a dependent clause?
Answer: A dependent clause cannot stand alone in a sentence, but a phrase can.
Question 4
A) Which choice best describes the function of phrases and clauses?
Answer: to add detail and meaning.