Question: In a UICC with a present GSM application, where is the first EFCCP1 (identified by '6F4F') of the DFPHONEBOOK mapped to ensure backwards compatibility, and what implication does this have for a 3GPP Mobile Equipment (ME)?
Option 1: Mapped to DFGSM, allowing direct access by both GSM and 3GPP MEs.
Option 2: Mapped to DFTELECOM, but accessible to 3GPP MEs only through EFCCP under DFGSM.
Option 3: Not mapped, as backwards compatibility for phonebook is not a requirement in 3GPP MEs.
Option 4: Mapped to DFTELECOM, ensuring GSM compatibility, with the information accessible to 3GPP MEs via EFCCP1 under DFPHONEBOOK.
Explanation: To maintain backwards compatibility with GSM applications on a UICC, the first EFCCP1 ('6F4F') of the DFPHONEBOOK is mapped to DFTELECOM. This prevents potential inconsistencies if a GSM terminal accessed or modified an EFCCP directly under DFTELECOM. As a result, 3GPP Mobile Equipment (ME) retrieves necessary information through EFCCP1 under DFPHONEBOOK, ensuring seamless functionality across both GSM and 3GPP platforms.