Question

What is the main rationale that Brutus gives in his act 2.1 soliloquy in The Tragedy of Julius Caesar to explain his involvement in the assassination plot against Caesar?

Caesar will not become a tyrant because Brutus has never seen Caesar behave as a tyrant.
Caesar will become a tyrant because Caesar has the hallmarks of a tyrant and power will allow him to behave as a tyrant.
Caesar will not become a tyrant because Caesar is a nice guy without any tyrannical tendencies.
Caesar will definitely become a tyrant because Caesars' gentle personality will allow him to be corrupted.