Select the correct answer. What is the role of dialogue in the following excerpt from Frances Hodgson Burnett's A Little Princess?

The change in her life did not come about gradually, but was made all at once.

"She must begin as she is to go on," Miss Minchin said to Miss Amelia. "She must be taught at once what she is to expect."

Mariette had left the house the next morning. The glimpse Sara caught of her sitting room, as she passed its open door, showed her that everything had been changed. Her ornaments and luxuries had been removed, and a bed had been placed in a corner to transform it into a new pupil's bedroom.

When she went down to breakfast she saw that her seat at Miss Minchin's side was occupied by Lavinia, and Miss Minchin spoke to her coldly.

"You will begin your new duties, Sara," she said, "by taking your seat with the younger children at a smaller table. You must keep them quiet, and see that they behave well and do not waste their food. You ought to have been down earlier. Lottie has already upset her tea."

A.
It resolves a conflict.
B.
It supports and develops a theme.
C.
It advances the plot.
D.
It reveals information about the setting.
I think it's B but i'm not sure