Always give NPCs you're negotiating with a choice of options. After all, you want to appear reasonable.
Just make sure that the option your prefer is accompanied by options that are even more undesirable from the NPC's point of view.
Palpatine: Ah, Anakin; I've been trying to reach you for several minutes.
Palpatine: Is Gunray—
Anakin: Dead? Yes.
Palpatine: And the rest of the Separatist lead—
Anakin: Dead. All of them.
Palpatine: I have addressed the Senate; I have the authority to use the clone army for whatever peacekeeping mission—
Anakin: Unnecessary. The cyborg abominations answer to me now. They were already building our glorious Peace Moon. I saw no reason to stop them.
Palpatine: Well; good then...
Anakin: I suggest you deal with the diplomacy, while I lead our armies to victory over the last of the resistance.
Palpatine: Um... yes, but—
Anakin: Or I could do the diplomacy if you like.
Palpatine: Let's go with the first option.