Pass data from one activity to another Android

package app.mobiledevicesecurity;

import java.util.List;

import android.app.Activity;
import android.content.Intent;
import android.graphics.Typeface;
import android.media.MediaPlayer;
import android.os.Build;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;

public class Quiz extends Activity
{
    List<question> questionList;
    int score = 0;
    int qid = 0;
    Question currentQuest;
    TextView txtQuestion, scored;
    Button button1, button2, button3;

    @Override
    protected void onCreate(Bundle savedInstanceState)
    {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_quiz);
        QuizHelper db = new QuizHelper(this);
        questionList = db.getAllQuestions();
        currentQuest = questionList.get(qid);
        txtQuestion = (TextView) findViewById(R.id.txtQuestion);

        button1 = (Button) findViewById(R.id.button1);
        button2 = (Button) findViewById(R.id.button2);
        button3 = (Button) findViewById(R.id.button3);

        scored = (TextView) findViewById(R.id.score);



        setQuestionView();

        button1.setOnClickListener(new View.OnClickListener()
        {
            @Override
            public void onClick(View v) {
               getAnswer(button1.getText().toString());
            }
        });

        button2.setOnClickListener(new View.OnClickListener()
        {
            @Override
            public void onClick(View v) {
                getAnswer(button2.getText().toString());
            }
        });

        button3.setOnClickListener(new View.OnClickListener()
        {
            @Override
            public void onClick(View v) {
                getAnswer(button3.getText().toString());
            }
        });
    }
    public void getAnswer(String AnswerString)
    {
        if (currentQuest.getAnswer().equals(AnswerString))
        {
            score++;
            scored.setText("Score : " + score);
        }
        else
        {

            Intent intent = new Intent(Quiz.this,
                    Result.class);
            Bundle b = new Bundle();
            b.putInt("score", score);
            intent.putExtras(b);
            startActivity(intent);
            finish();


        }
        if (qid < questionList.size()) {
            currentQuest = questionList.get(qid);
            setQuestionView();
        }
        else
        {

            Intent intent = new Intent(Quiz.this,
                    Result.class);
            Bundle b = new Bundle();
            b.putInt("score", score);
            intent.putExtras(b);
            startActivity(intent);
            finish();


        }
    }

    private void setQuestionView()
    {
        txtQuestion.setText(currentQuest.getQuest());
        button1.setText(currentQuest.getOption1());
        button2.setText(currentQuest.getOption2());
        button3.setText(currentQuest.getOption3());
        qid++;
    }
}

package app.mobiledevicesecurity;

import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;

public class Result extends Activity {

    private static Button playbtn;
    private static Button menubutton;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_result);
        OnClickPlayButtonListener();
        OnClickMenuButtonListener();
        TextView textResult = (TextView) findViewById(R.id.textResult);
        Bundle b = getIntent().getExtras();
        int score = b.getInt("score");
        textResult.setText("You scored" + " " + score + " for the quiz.");

        Intent intent2 = new Intent(Result.this,
               Scores.class);
        Bundle bun = new Bundle();
        bun.putInt("score", score);
        intent2.putExtras(bun);
        startActivity(intent2);
        finish();
    }

    public void OnClickPlayButtonListener() {
        playbtn = (Button) findViewById(R.id.btn);
        playbtn.setOnClickListener(
                new View.OnClickListener() {
                    @Override
                    public void onClick(View v) {
                        Intent intent = new Intent("app.mobiledevicesecurity.Quiz");
                        startActivity(intent);
                    }
                }
        );
    }

    public void OnClickMenuButtonListener() {
        menubutton = (Button) findViewById(R.id.menubtn);
        menubutton.setOnClickListener(
                new View.OnClickListener() {
                    @Override
                    public void onClick(View v) {
                        Intent intent = new Intent(getApplicationContext(), MainActivity.class);
                        startActivity(intent);
                    }
                }
        );
    }
}

package app.mobiledevicesecurity;

import android.support.v7.app.ActionBarActivity;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;



import android.widget.TextView;
import android.content.Intent;

public class Scores extends ActionBarActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_scores);

        TextView txtScore1 = (TextView) findViewById(R.id.txtScore1);
        Bundle bun = getIntent().getExtras();
        int score = bun.getInt("score");
        txtScore1.setText("score:" + " " + score + " for the quiz.");
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.menu_scores, menu);
        return true;
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        // Handle action bar item clicks here. The action bar will
        // automatically handle clicks on the Home/Up button, so long
        // as you specify a parent activity in AndroidManifest.xml.
        int id = item.getItemId();

        //noinspection SimplifiableIfStatement
        if (id == R.id.action_settings) {
            return true;
        }

        return super.onOptionsItemSelected(item);
    }
}