To identify the physical fruit juice preservation methods, we need to classify the given techniques as physical processes.
- Refrigeration (A): A physical method that reduces microbial activity through cooling.
- Salt addition (B): A chemical method that alters the juice's chemical environment.
- Sugar addition (C): A chemical method that modifies osmotic balance rather than being a physical process.
- Pasteurization (D): A physical method that eliminates microorganisms by heating.
Therefore, the physical preservation methods are Refrigeration (A) and Pasteurization (D). The correct identification is: (A) and (D) only.