Final answer:
The three principal stages of testing for a commercial software system are prototype testing, refinement testing, and final testing.
Step-by-step explanation:
The three principal stages of testing for a commercial software system are:
- Prototype Testing: In this stage, prototypes of the software are tested to assess whether the design meets all constraints and performs acceptably according to the specified criteria.
- Refinement Testing: After evaluating the prototypes, weaknesses in the design may be revealed, and improvements can be made to better meet the specified criteria and constraints.
- Final Testing: This stage involves comprehensive testing to ensure that the software functions properly, meets all requirements, and is free from errors or bugs.