Which of the following sentences is punctuated correctly?

李老师

Which of the following sentences is punctuated correctly?
A. Mary graduated in four years but she didn't find a job immediately.
B. It was a large, black, Labrador retriever.
C. Mary who is my sister will be at the party too.
D. all of the above
E. none of the above
2. Which of the following sentences is punctuated correctly?
A. I just read the novel A Simple Plan.
B. Heather Hardy, Ph.D., is the director of undergraduate studies in our department.
C. He had only one desire in life: to catch a ten-pound bass.
D. all of the above
E. none of the above
3. Which of the following sentences is punctuated correctly?
A. No one expected her to buy a car, so we were quite surprised when we discovered that she had bought two.
B. No one expected her to buy a car, so we were quite, surprised when we discovered that she had bought two.
C. No one expected her to buy a car, so we were quite surprised when we discove