Hi Tejas,
Here you go:
Add reference to Newtonsoft.Json;
using Newtonsoft.Json;
Here the code to get Country:
WebClient wc = new WebClient();
var jsonStr = wc.DownloadString("http://maps.googleapis.com/maps/api/geocode/json?latlng=17.37528,78.47444&sensor=false");
JObject a = JObject.Parse(jsonStr);
var addresses = a["results"][0]["formatted_address"].ToString();
var country = addresses.Split(',')[(addresses.Split(',').Length - 1)].Trim();
Hope it helps.
Happy Coding :)