Yes, GSN did not properly phrase the question, BUT THE CORRECT ANSWER IS 2002
Mace Windu deals the death blow in the Geonosian arena in Attack of the Clones. Mace Windu, using the lightsaber technique Vapaad.
yes, on geonosis, in the arena. near the end.
On Geonosis. That's where a variety of battledroids are made. Plus it is the first planet to create the awesome super battledroids and star plans for the Death Star, i hope this answer has been...
He announced the beginning of the Clone Wars. Remember he said: "Begun the Clone War has."