正解:B
To access the list of VLANs received via the API call, the programmer should use the key 'Vlan1' within the VlanNames dictionary. This method allows for direct access to the specific VLAN information required.
References := The explanation is derived from the Implementing and Operating Cisco Service Provider Network Core Technologies training, which covers topics such as networking, automation, and quality of services, relevant to handling VLANs and API calls