Please provide a clear explanation and an answer for part B.

As the production planner for Xiangling Hu Products, Inc., you have been given a bill of material for a bracket that is made up of a base, 2 springs, and 4 clamps. The base is assembled from 1 clamp and 2 housings: handle and 1 casting. Each housing has 2 bearings and 1 shaft. There is no inventory on hand. h clamp has 1 Click the icon to view the product structure. Your boss at Xiangling Hu Products, Inc., has just provided you with the schedule and lead times for the bracket. The unit is to be prepared in week 11. The lead times for the components are bracket ( 1 week), base ( 1 week), spring (1 week), clamp ( 1 week), housing ( 3 weeks), handle ( 2 weeks), casting ( 4 weeks), bearing ( 1 week), and shaft ( 1 week). a) Choose the correct time-phased product structure for the bracket. A. B. B. c. c. D. b) In what week do you need to start the castings? handle and 1 casting. Each housing has 2 bearings and 1 shaft. There is no inventory on hand. Click the icon to view the product structure. Your boss at Xiangling Hu Products, Inc., has just provided you with the schedule and lead times for the bracket. The unit is to be prepared in week 11. The lead times for the components are bracket (1 week), base (1 week), spring (1 week), clamp (1 week), housing ( 3 weeks), handle ( 2 weeks), casting ( 4 weeks), bearing (1 week), and shaft (1 week). a) Choose the correct time-phased product structure for the bracket. A. B. B. C. D. b) In what week do you need to start the castings? The castings need to be started in week (enter your response as a whole number)