What is the output of below snippet? public class Demo { public static void main(String[] args) { Map sampleMap = new TreeMap(); sampleMap.put(1, null); sampleMap.put(5, null); sampleMap.put(3, null); sampleMap.put(2, null); sampleMap.put(4, null); System.out.println(sampleMap); } }

• A. {1=null, 2=null, 3=null, 4=null, 5=null}
• B. {5=null}
• C. Exception is thrown
• D. {1=null, 5=null, 3=null, 2=null, 4=null}