1) I am pretty sure that the problem which contributed to Rome's transition from a republic to an empire is being revealed by the option one : consuls staying in power too long. I choose this option because only this option is closely connected with main characters from this event : Marius, Sulla, and the Triumvirs.
2) The thing which Julius Caesar did that hastened Rome's transition from a republic to an empire is being shown in the option : He crossed the Rubicon and defeated his enemies. I think this is correct because he let a civil war out towards republic.
Do hope you sill need the answer because this one will definitely help you!
