I would say the 2nd to last paragraph the on that starts with "He"
The line that best states that Juliet is too young to get married is Capulet's first line. "But say o'er what I had said before: My child is yet a stranger in the world; She hath not seen the change of fourteen years, Let two more summers wither in their pride, Ere we may think her ripe to be a bride."
Capulet is saying that Juliet is not familiar with what goes on in the world and that within her lifetime, she hasn't seen the change around her. He's saying that he wants her to spend two more summers at most, because he thinks she's too young to marry.
Hope this helps!
Signed, Liz
Since the 'inciting incident' is the one which starts all the problems in a literary work, the answer is B, 'establishment of the central conflict followed by the conflict increasing and a climax'.