using System;

using Newtonsoft.Json;

using Newtonsoft.Json.Linq;

public class Program

{

    public static void Main()

    {

        string s = @"

            {

              ""id"": 78,

              ""results"": [

                {

                  ""iso_3166_1"": ""US"",

                  ""release_dates"": [

                    {

                      ""certification"": ""R"",

                      ""iso_639_1"": """",

                      ""note"": """",

                      ""release_date"": ""1982-06-25T00:00:00Z"",

                      ""type"": 3

                    }

                  ]

                },

                {

                  ""iso_3166_1"": ""FI"",

                  ""release_dates"": [

                    {

                      ""certification"": ""K-16"",

                      ""iso_639_1"": """",

                      ""note"": """",

                      ""release_date"": ""1982-10-01T00:00:00Z"",

                      ""type"": 3

                    }

                  ]

                }

              ]

            }";

​

        var obj = JsonConvert.DeserializeObject<JObject>(s);

        var resultArr = (JArray)obj["results"];

        foreach (JObject resultObj in resultArr)

        {

            var releaseDatesArr = (JArray)resultObj["release_dates"];

            foreach (JObject releaseDateObj in releaseDatesArr)

            {

                var _currentMPAARating = (string)releaseDateObj["certification"];

                Console.WriteLine(_currentMPAARating);

            }

        }   

    }

}