Before moving out of their apartment, Kelly and Doug decided to have their carpets cleaned by Stanley Steemer, a company specializing in professional carpet cleaning. The carpet cleaners arrived on time, cleaned the carpets, and drove away in their bright yellow van. Only then did the couple see that they did a good job. Kelly and Doug were unable to judge the service before they bought it, which illustrates the of services. a. inconsistencyb. inseparabilityc. inventory costsd. intangibilitye. interdependence