Final answer:
The I/O model is grounded in psychology, particularly in the organizational psychology subfield, which focuses on job satisfaction and how to motivate workers.
Step-by-step explanation:
The I/O model, which stands for Industrial/Organizational model, is grounded in psychology. This field is interested in understanding the psychology of workers to help organizations become more productive and competitive. Industrial/Organizational psychology is concerned with how to motivate workers for high productivity and efficiency, as well as understanding the psychological complexity of diverse workforces. The area of I/O psychology that measures job satisfaction is known as organizational psychology.