Answer:
d) research and development
Step-by-step explanation:
The three primary functions of an organization are finance and accounting, because you need at least organize your accountability to know their performance of your business in money terms and also because the law of the countries demand it to declare taxes. The marketing, is the way of how you are going to promote your products and finally affects directly to the revenue, and production and operations are the way as you produce and organize your products and deliveries Those three areas are essential for any business regarless of their size.
The research and development usually is an area that you create and implement in your business when you have more resources.