VCE. You would be clicking varlinks to either say Yes or no, and depending on what you pick, different things happen.
I would not suggest varlinks, because of a glitch where if the player does not have VCE, varlinks don't work for them. As Wisp suggested, prompt events would work well, or you can even use OnPlayerTalk coupled with LocalChat and VCE to not be limited to "yes or no" but options, like "Run, Hide, Fight, stuff your pants".
Also, with the OnPlayerTalk option, client messages can be made extra pretty with color and don't changes, and you wouldn't have those ugly cyan, underlined links and prompt boxes.