Null pointer exception using gson to parse json

Using Gson, I am trying to parse below json, but getting null pointer exception. Please find below class objects to load json output.

json file:

{
  "q1": {
    "question": "Which one is correct team name in NBA?",
    "options": [
      "New York Bulls",
      "Los Angeles Kings",
      "Golden State Warriros",
      "Huston Rocket"
    ]
  }
}

Data class to load q1:

public class Data {
    Q1 q;
}

Q1 class to load json data inside q1:

public class Q1 {

    String question;
    List<String> options;
    String answer;

}

Runner class to parse the data:

public class ParseData {

    public static void main(String[] args) throws IOException {

        String dataAsString = new 
        String(Files.readAllBytes(Paths.get("data.json")));
        System.out.println(dataAsString);

        Gson gson = new Gson();
        Data data = gson.fromJson(dataAsString, Data.class);
        System.out.println("printing question ... "+data.q.question);

    }

}

Can someone please help, thanks in advance.