Refer to the exhibit. A network engineer troubleshoots an issue with the port channel between SW1 and SW2. Which command resolves the issue?

While `switchport mode trunk` is typically needed for aggregated links, the immediate issue preventing the port channel from forming is the LACP negotiation failure due to mismatched LACP modes.

SW2 is configured with `channel-group 10 mode passive` for LACP, meaning it will listen for LACP packets but not initiate them. For the port channel to form, SW1 must be configured with `channel-group 10 mode active` to actively send LACP packets and negotiate the bundle, satisfying the `passive` peer.

Configuring SW1 to `desirable` mode uses PAgP, not LACP; since SW2 is configured for LACP `passive`, the protocols would not match, and the port channel would not form.

Configuring SW2 to `on` mode puts it into an unconditional EtherChannel, which requires the peer to also be in `on` mode; this would not work with SW1 in LACP `active` or `desirable`.