After losing all his savings in the stock market crash, he found himself in an ____________ state, relying on charity for survival.
Correct: C
The context describes someone who lost all savings and is relying on charity, indicating extreme poverty. 'Impecunious' means having little or no money; poor. This is the most suitable word. 'Opulent' and 'affluent' mean wealthy, which are antonyms. 'Solvent' means able to pay one's debts, which is the opposite of the described state.