1. An information processing apparatus which processes structured language data, the apparatus comprising: a processor and a memory configure to function as: an acquisition unit configured to acquire structured language data as a processing target via one of a first interface and a second interface which differ physically or differ logically from one another, wherein said acquisition unit can acquire the structured language data via any of the first interface and the second interface; a storage unit configured to store a first style sheet and a second style sheet which respectively correspond to the first interface and the second interface and define processing methods, different from each other, for generating an image based on the structured language data acquired by said acquisition unit; a selection unit configured to select the first style sheet in a case where the first interface is used for the acquisition of the structured language data by said acquisition unit, and to select the second style sheet in a case where the second interface is used for the acquisition of the structured language data by said acquisition unit; and a processing unit configured to generate an image based on the structured language data as a processing target acquired by said acquisition unit in accordance with a processing method defined in the style sheet selected by said selection unit among the first style sheet and the second style sheet stored by said storage unit, wherein said processing unit executes the processing based on the selected style sheet in either case that the first style sheet or the second style sheet is selected by the said selection unit.