The correct answer is C. 8000 units.
Budget production is the number of units that a company plans to produce in a given period of time. It is calculated by taking the budget sales units and adding the desired ending inventory, and then subtracting the beginning inventory.
In this case, the budget sales units are 5000, the desired ending inventory is 4000, and the beginning inventory is 1000. Therefore, the budget production is:
Budget production = 5000 + 4000 – 1000 = 8000 units
Option A is incorrect because it is the beginning inventory, not the budget production.
Option B is incorrect because it is the budget sales units, not the budget production.
Option D is incorrect because it is the sum of the budget sales units and the beginning inventory, not the budget production.