What about Gatsby's parties indicate that he is wealthy?

In the great Gatsby chapter 3

We are told that Gatsby came up from essentially nothing, and that the first time he met Daisy Buchanan, he was “a penniless young man.” His fortune, we are told, was the result of a bootlegging business – he “bought up a lot of side-street drug-stores here and in Chicago” and sold illegal alcohol over the counter.Jay Gatsby's parties symbolize the shallowness of the upper class in The Great Gatsby. Gatsby's parties were the hub for upper-class society. ... It shows the shallowness of the upper-class and the fact that they are obsessed with wealth.

Advice: try reading the book

idk

explanation:

i think the answer would mist likely be an adjective clause, because unhappy is an adjective.