When is the B object, created in line 3, eligible for garbage collection? void start() { A a = new A(); B b = new B(); a.s(b); b = null; /* Line 5 */ a = null; /* Line 6 */ System.out.println("start completed"); /* Line 7 */ }

• after line 5
• after line 6
• after line 7
• There is no way to be absolutely certain.