Final answer:
A computer network documentation or a network diagram can be used to obtain information on LINE/TRUNK/CHANNEL.
Step-by-step explanation:
The resource that can be used to obtain information on LINE/TRUNK/CHANNEL is a computer network documentation or a network diagram. These diagrams are used to visually represent the connections and relationships between different network devices and components, including lines, trunks, and channels. They provide a comprehensive overview of the network infrastructure and help in troubleshooting, planning, and documenting the network.