The data indicates that for the Mercedes-Benz C-Class (2014-19) C250 4DR Saloon with the specified trim, all vehicles are equipped with a 2.1-liter diesel engine. This consistent engine capacity underscores a uniform engine specification across the sample, with diesel as the sole primary fuel type used. Such homogeneity suggests a standard engine configuration within this model range, which can be useful for buyers or technicians seeking specific engine and fuel information.