A collaboration engineer is configuring the QoS trust boundary for Cisco UCM voice and video conferencing. Which two trust boundary configurations are valid? (choose two)

Extending QoS trust boundaries to all devices directly attached to access switch ports is too broad and risky, as many end devices cannot be trusted to mark traffic correctly.

Extending QoS trust boundaries directly to Jabber running on a PC is not recommended due to the untrusted nature of PC operating systems and their susceptibility to QoS marking manipulation.

A PC running Jabber softphone is generally considered an untrusted device because the PC operating system and other applications can manipulate QoS markings, potentially causing a security or policy violation, making it unsuitable for a QoS trust boundary.

The QoS trust boundary can be extended to dedicated voice and video devices that reliably mark traffic, especially when a PC is connected through the voice VLAN port of such a device, allowing the IP phone to apply the QoS markings before passing the traffic to the PC.

Stating that QoS trust boundaries can be extended to voice and video devices exclusively is not entirely accurate, as the boundary typically starts at the IP phone and the decision to extend depends on specific network design and trust models for other devices.