The correct answer is: A. determine the production schedule.
Once net requirements have been calculated, the next step is to determine the production schedule. This involves determining the quantity of each item to be produced, the time period over which production will take place, and the resources that will be required. The production schedule is then used to create a detailed plan for the production process.
Option B is incorrect because machine and manpower requirements are determined as part of the production planning process, which takes place before net requirements are calculated.
Option C is incorrect because gross requirements are calculated before net requirements. Gross requirements are the total demand for an item, taking into account both independent and dependent demand.
Option D is incorrect because the production process does not start until the production schedule has been created.
Option E is incorrect because it is not one of the steps in the production planning process.