In order to determine what is the most accurate description of the given study, you take into account the following definitions:
- A single-blind experiment is one in which only the researchers know the treatement that participants of the study are receiving.
- A double-blind experiment is one in which neither the participants of the study nor the researchers know who is receiving a particular treatment.
- In an observation a researcher only tries to identify important features of a specific situation, without intercat with participants.
- In an experiment, researcher construct different kinds of situation in which they can point out relation between causes and effects.
According to the previous definitions, you can conclude that the most accurate description of the study that bakery makes, is the single-blind experiment. This is because the bakery knows the type of aples of each apple pie while people don't. This corresponds to a case in which only researcher know the treament that the participants receive.