the correct answer is D: They are about to kill him.
The conspirators gathered round Caesar, Metullus present on his knees as a petition to Caesar, to pardon his banished brother. Brutus, Cassius, Cinna and Decius also ask on their bended knees, but Caesar refuses to change his decree and be merciful, likening himself to the constant and true-fixed north pole star. At this point the conspirators strike, stabbing Caesar to death.
It's been a while since I read Caesar (like a few months), but the conspirators made sure to arrange a meeting with Caesar so they could assassinate him against his knowledge (sorta, I think he suspected they would kill him)
