Question: In a 3GPP Network Domain Security (NDS) context, which of the following Diffie-Hellman groups for ECDHE is not recommended to be supported according to the specified TLS 1.2 profiling?
Option 1: secp256r1 (P-256)
Option 2: secp384r1 (P-384)
Option 3: curve25519
Option 4: Elliptic curve groups of exactly 192 bits
Explanation: According to the TLS 1.2 profiling for NDS, for ECDHE, elliptic curve groups with less than 256 bits are not recommended, making exactly 192 bits not supported, as secp256r1 and secp384r1 are preferred, with a specific exemption not applying to this answer choice.