Answer: Option D
Explanation: In simple words, customized service refers to those tailor made services that are prepared by the producers on the basis of needs and preferences of a particular customer.
These services generally require higher amount of time and resources to get prepared thus it cost higher to the users as compared to standardized services.
These service are more flexible than standardized services as they are made on the specification of a particular customer who while ordering specifies the flexibility that he or she might need in future.
Hence from the above we can conclude that the correct option is D.