Explanation:

- "Opulent" means rich, luxurious, or wealthy.

- Option 1, Insolvent: Means unable to pay debts; often financially broken, but it's more about being bankrupt, not necessarily the direct opposite of wealth or luxury.

- Option 2, Flourishing: Means thriving or doing well; it is similar to opulent in a positive sense, so not an antonym.

- Option 3, Depressed: Means sad or low in spirits; this is about emotions, not wealth or luxury.

- Option 4, Destitute: Means extremely poor, lacking the basic necessities of life. This is directly opposite to opulent, which implies great wealth.

Correct Answer: Option 4, Destitute