Final answer:
Carlos's action of baking and selling sample goods pre-opening represents the 'testing a hypothesis by experiment' stage of the scientific process, mirroring the methodical approach used in scientific inquiry.
Step-by-step explanation:
When Carlos baked a variety of sample cupcakes and cookies to sell at local farmers markets and other events before opening his new bakery, this represents the stage of the scientific process where he is testing a hypothesis by experiment. The scientific method consists of making observations, formulating hypotheses, and designing experiments to test these hypotheses. By trying out his baked goods in the market, Carlos is effectively conducting an experiment to see if his products will be well-received and if there is a demand for them. This process is analogous to a laboratory experiment where scientists conduct experiments to test hypotheses under controlled conditions.