The correct option is "Only two pairs" because, among the given locations, only Dhauli in Odisha and Jaugada in Odisha are sites of Ashoka’s major rock edicts. The sites of Kalsi and Erragudi are incorrectly matched as Kalsi is located in Uttarakhand, while Erragudi is not a recognized location for Ashoka’s edicts. The significance of these inscriptions lies in their historical importance, as they reflect Ashoka's efforts to promote Buddhism and moral governance, which are crucial topics in UPSC Prelims GS Paper I under Indian History and Culture.