After the following program is finished, how many bytes are written to the file t.dat?

import java.io.*; public class Test { public static void main(String[] args) throws IOException { DataOutputStream output = new DataOutputStream( new FileOutputStream("t.dat")); output.writeChars("ABCD"); output.close(); } } 

2 bytes.

4 bytes.

8 bytes.

12 bytes.

16 bytes.