Answer:
Have you read the Great Gatsby ?
I think the author chose to start the book 19 years before the main events of the story so the reader could absorb things. The author technically wanted the reader(s) to understand something before reading the real story.
It's not a. obviously because he doesn't know that she and her father fought over her not wanting to marry him. It's not b. because he acts like she is already his wife and I quote says "Till then, adieu, and keep this holy kiss." It isn't c. because the whole reason her father insisted he marry her so quickly was because of her deep grieving over "Tybalt", which concludes that the answer is d. (Sorry just wanted to be thorough so you wouldn't be confused.)
The difference is that food can be like a salad. And a meal is like chicken with rice and a drink. I hope this helped!