Product A is made from components B and C. Item B, in turn, is made from D and E. Item C also is an intermediate item, made from F and H. Finally, intermediate item E is made from H and G. The following are item lead times in weeks: Item A B D E F G H Lead time 5 7 2 6 5 6 4 3 3 What is the customer response time if all purchased items (i.e., D, F, G, and H) are in inventory? Select one: O 19 O 18 21 17 7