REST API Does not return JSON

Hi,

Currently I am Writing a Console Application Which should return JSON but It is not. instead it is returning me XML.

System.Net.Http.HttpClient _Client = new System.Net.Http.HttpClient();
            _Client.BaseAddress = new Uri("http://test/sites/abc");
            _Client.DefaultRequestHeaders.Add("accept", "application/json; odata=verbose");

any idea what is wrong ?

Thanks, Parth