Sean moved to take a new job, and when he got sick he needed to find a doctor. He discovered during the visit that he didn't like the one he had chosen, and he knew he'd never go back to that doctor. From a marketing perspective, his situation highlights one of the key differences between products and services, known as
A. intangibility.
B. professional competence.
C. perishability.
D. inseparability.
E. heterogeneity.
Answer: D. inseparability