What Does the Following Statement Sequence Print If the User

Multiple Choice

What does the following statement sequence print if the user input is 123? public static void main(String[] args)
{
Scanner in = new Scanner(System.in) ;
System.out.print("Enter a number: ") ;
String str = in.next() ;
Str += 456;
System.out.println(str) ;
}

A) 579
B) Compile-time error
C) Run-time error
D) 123456