JsonObject Deserialization

Question

We are trying to deserialize Bitly data and select some values using linq operators. But it shows System.Nullreference.Exception in anonymous class

Below is our code

static void Main(string[] args)
{
    var fileData = File.ReadAllLines("bitlyfile.txt");
    var singleRow = fileData.Select(ToJson).ToList();
    singleRow.ToList().ForEach(Print);

    singleRow
       .GroupBy(b => b.Country)
       .OrderByDescending(g => g.Count())
       .Take(10)
       .Select(g => new { CountryName = g.Key, Users = g.Count() })
       .ToList()
       .ForEach(Print);

    Console.ReadKey();
}

public static Bitly ToJson(string json)//
{
    return JsonConvert.DeserializeObject<Bitly>(json);
}
public static void Print(object obj)
{

    Console.WriteLine(obj);
}

class Bitly
{
    [JsonProperty("c")]
    public string Country { get; set; }
    public override string ToString()
    {
        return Country;
    }
}

Here is our bitly file :Bitly File

It showing an error like below in the line as b is null

.GroupBy(b => b.Country)