What will be the output of the program?

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 '); 
    } 
}