Marla, a bookkeeper, would like to work at home in order to be with her young children. but before setting up her home-based bookkeeping service, she should

The Answer may well be: D. Investigate the Market

So when we are determining the production possibilities curve, the amount of productive resource remain constant or at least an assumption is made that the amount of resources is fixed while deriving the curve. This is done that way because to avoid fluctuations in the curve while analyzing the curve.