10. An apparatus according to claim 1 , further comprising a memory that stores fonts of languages of a plurality of countries, wherein the control unit generates the display signal of the authenticating display screen by using the font of the decided display language among the fonts stored in the memory.
11. An apparatus according to claim 10 , wherein if the font of the language of the country decided based on the communication carrier identification information is not stored in the memory, the control unit controls the interface unit so as to read out the information of the font from the storage medium and controls the display unit to generate the display of the authenticating display screen by using the read-out font.