How was julius caesar able to defy the senate, cross the rubicon, and engage in a civil war with his enemies

By developing great connections with people, been an amazing leader and gathering enough military power to stand against anyone. His army made him do it.

Explanation:

Julius Ceaser was a very intelligent man, he was a very empathic leader who understood the needs of his people. He developed the ability to listen to them and to provide them with the right stuff. The people followed him because of it and they became loyal to him because they understood he was a good provider, protector, and visionary. After his enemies understood the danger he represented to them, they decided they had to do something against him the thing was that it was already too late because he could foresee what they were going to do and decided to react. Julius Ceasar knew they were corrupt and bureaucratic, he was a practical man and considered he was a better choice for the people, as well as them. All this lead him to gather an incredibly military force with amazing loyalty.

c. pro-democracy demonstrations.

the correct answer is c.