Final answer:
The service best described as having high customer interaction and labor intensity is a Chiropractor, due to the necessity of hands-on treatment and one-on-one time.
Step-by-step explanation:
The service offering best described by having a high degree of customer interaction and high labor intensity is D) Chiropractor. This service requires significant one-on-one time with the client for assessment, treatment, and advice, as well as a substantial amount of physical labor in manually adjusting the spine and other parts of the body. Compared to the other options, a chiropractic service has a higher degree of both customer interaction and labor intensity, as it largely depends on the skilled labor and expertise of the chiropractor during the service encounter.