The owner of a store that sells fine-quality fabrics for home seamstresses bemoans the fact that few young women know how to do fine tailoring, much less simple dressmaking. many potential customers are unable to appreciate the premium quality of the fabrics and are deterred by the high prices, as well as the complexity of fine sewing. in the past, the store had a strong demand for fabrics, large classes for women learning the fine points of sewing, and a reputation for excellent service and technical advice. now the store is earning lower-than-average returns. this case is an example of: a. core competencies that have become core rigidities. b. the lack of intangible resources undermining the core competencies of the firm. c. the hazard of competitors being able to imitate a firm's core competency. d. the need for firms to stick to their core competencies through temporary downturns in market demand.