Option D, Demand forecasting is performed at the time of aggregate planning.
Explanation:
Aggregate planning is a marketing operation which, before 6-18 months, makes the aggregate production planning to give management a concept of the number of components to obtain and when to keep the total costs of the organization's operations to a minimal level over that period.
These are the steps to build an aggregate plan:
Step 1: Recognize the aggregate plan for your firm: level, chase.
Step 2: Determine the overall production rate on the basis of the aggregate plan.
Step 3: Calculate employee scale.
Step 4: The overall plan should be tested.
Step 5: Evaluate the quality of the project in terms of price.
"Demand forecasting" implies forecasting demand for the product of a particular company.
For example, Birla cement demand, Raymond clothes demand, etc.