Question: When a Mobile Station (MS) supports Single Radio Voice Call Continuity (SRVCC) to GERAN, what additional information does it send to the Serving GPRS Support Node (SGSN) in Attach Request/Routeing Area Update Request messages in both Iu mode and A/Gb mode?
Option 1: Only CS domain's Classmark 2 information element
Option 2: Only CS domain's Classmark 3 information element
Option 3: Both CS domain's Classmark 2 and Classmark 3 information elements
Option 4: Neither Classmark 2 nor Classmark 3, only MS Radio Access Capability
Explanation: This is because, for SRVCC to GERAN, the Mobile Station (MS) must send both CS domain's Classmark 2 and Classmark 3 information elements to the SGSN in these messages, ensuring seamless voice call continuity by providing necessary capabilities for effective handover management between different radio access technologies (RATs).