Can you explain why is the answer is D here?

7. What is returned by the following Scheme statement? (cons (1 2 3) (cons (4 5 6) ()) 2. (1 2 3 456) (1 2 3 (45 6)) (123) 4 56) ((1 2 3) (4 5 6) (1 (2 3) 45 6) (1 (2 3) (456)) None of these A. B. C. inh 1 (123) i (as(-)) E. F. G