title: Converting NSData to NSDictionary
body: <p>I am trying to fetch data from an url <a href="https://dl.dropboxusercontent.com/s/2iodh4vg0eortkl/facts.json" rel="noreferrer">https://dl.dropboxusercontent.com/s/2iodh4vg0eortkl/facts.json</a></p>
  
  <p>I am getting nil while converting nsdata to nsdictionary.</p>
  
  <p>I used the following code. and I am able to log the data as well. but as soon as I convert it into dictionary it is showing nil.What am I missing here?</p>
  
  <p>I tried nsurlsession and afnetworking as well. getting the same error.</p>
  
  <pre><code>NSError *error;
  NSString *url_string = [NSString stringWithFormat: DATA_URL];
  NSData *data = [NSData dataWithContentsOfURL: [NSURL URLWithString:url_string]];
  NSDictionary *json = [NSJSONSerialization JSONObjectWithData:data options:kNilOptions error:&amp;error];
  NSLog(@"json: %@", json);
  </code></pre>