This is a personal question. I will answer below according to the word that was unfamiliar to me, but feel free to add to the answer in case there were more for you.
Answer and Explanation:
The word that I found unfamiliar and whose meaning I did not know at first was "behest". I had never seen that word before. To understand its meaning, I looked for context clues. <u>The rest of the sentence in which "behest" appears functions as a clue to finding its meaning. It says that, at a person's behest, something happened: "the Exhibition dropped its superfluous rags and stripped itself. . ." As soon as I read this part, it made me think of the word "command." For instance, the sentence "At the general's command, the troops advanced" has a similar connotation to the one with "behest".</u>
To confirm my assumptions, I looked the word up online and found it indeed means "order" or "command".
The correct answer is this: SHE DIVULGES HER DISDAIN OF HIS SUPERFICIALITY.
To be superficial means to be shallow, to lack depth. From the passage given above, the man in the passage show his ignorance by revealing that he has never seen white elephants before and the reply that the girl gave him shows that, she dislike his ignorance in such matter.
The Flute hope this helps