The dialogue between Cassius and Casca in paragraphs 13 through 16 indicates -
A their determination to conspire against Caesar.
Step-by-step explanation:
In Act 1 Scene 3, Cassius is met by Casca on a fiery night right after the arrival of Caesar in the city.
Cassius talks about the ominous weather with Casca and first uses symbols to describe what it means to Rome. The things that he related include the fact that the weather means there will be 'ruinous state' in the future.
This is a double entente in the sense that he means that there will be bad weather as well as bad governance. Then he compares the weather to Caesar making the admission very clear.