What will be the output of the program?

String s = "hello"; 
Object o = s; 
if( o.equals(s) )
{
    System.out.println("A"); 
} 
else
{
    System.out.println("B"); 
} 
if( s.equals(o) )
{
    System.out.println("C"); 
} 
else
{ 
    System.out.println("D"); 
}

1. A
2. B
3. C
4. D

int i = (int) Math.random();

class Tree { } 
class Pine extends Tree { } 
class Oak extends Tree { } 
public class Forest1 
{ 
    public static void main (String [] args)
    { 
        Tree tree = new Pine(); 
        if( tree instanceof Pine ) 
            System.out.println ("Pine"); 
        else if( tree instanceof Tree ) 
            System.out.println ("Tree"); 
        else if( tree instanceof Oak ) 
            System.out.println ( "Oak" ); 
        else 
            System.out.println ("Oops "); 
    } 
}

public class StringRef 
{
    public static void main(String [] args) 
    {
        String s1 = "abc";
        String s2 = "def";
        String s3 = s2;   /* Line 7 */
        s2 = "ghi";
        System.out.println(s1 + s2 + s3);
    }
}

public class ObjComp 
{
    public static void main(String [] args ) 
    {
        int result = 0;
        ObjComp oc = new ObjComp();
        Object o = oc;

        if (o == oc)  
            result = 1;
        if (o != oc)  
            result = result + 10;
        if (o.equals(oc) )  
            result = result + 100;
        if (oc.equals(o) )  
            result = result + 1000;

        System.out.println("result = " + result);
    }
}

String d = "bookkeeper";
d.substring(1,7);
d = "w" + d;
d.append("woo");  /* Line 4 */
System.out.println(d);

interface Count 
{
    short counter = 0;
    void countUp();
}
public class TestCount implements Count 
{
    public static void main(String [] args) 
    {
        TestCount t = new TestCount();
        t.countUp();
    }
    public void countUp() 
    {
        for (int x = 6; x>counter; x--, ++counter) /* Line 14 */
        {
            System.out.print(" " + counter);
        }
    }
}

1. public int a [ ]
2. static int [ ] a
3. public [ ] int a
4. private int a [3]
5. private int [3] a [ ]
6. public final int [ ] a

public class X 
{ 
    public static void main(String [] args) 
    {
        try 
        {
            badMethod();  
            System.out.print("A"); 
        }  
        catch (Exception ex) 
        {
            System.out.print("B"); 
        }  
        finally 
        {
            System.out.print("C"); 
        }  
        System.out.print("D"); 
    }  
    public static void badMethod() {} 
} 

class X implements Runnable 
{ 
    public static void main(String args[]) 
    {
        /* Missing code? */
    } 
    public void run() {} 
}

try 
{
    Float f1 = new Float("3.0");
    int x = f1.intValue();
    byte b = f1.byteValue();
    double d = f1.doubleValue();
    System.out.println(x + b + d);
}
catch (NumberFormatException e) /* Line 9 */
{
    System.out.println("bad number"); /* Line 11 */
}