Configure the switchport trunk allowed vlan add 300 command on SW1 port-channel 1. EtherChannel configuration should be applied to the logical port-channel interface for trunk VLAN policy after the bundle exists. Adding VLAN 300 to the port-channel preserves existing allowed VLANs and updates the logical link consistently. Applying the command only to a physical member interface can create inconsistent configuration between the member and the port-channel. Replacing the allowed list instead of using add could also remove existing VLANs and interrupt traffic. Cisco CCNA 200-301 v1.1 Network Access expects engineers to configure EtherChannel as one logical interface once the channel is formed. The corrected answer is to configure switchport trunk allowed vlan add 300 on SW1 port-channel 1. That updates the trunk safely and avoids per-member inconsistency.