[Practice Question] Which 3 functions are performed by intermediary network devices..

FreddyIW

Hello, I want to ask about this question I got in my Networking Academy course .

Red color = correct answers

A host is accessing a Web server on a remote network. Which three functions are performed by intermediary network devices during this conversation? (Choose three.)

• regenerating data signals
• acting as a client or a server
• providing a channel over which messages travel
• applying security settings to control the flow of data
  
• notifying other devices when errors occur
• serving as the source or destination of the messages

Why isn't the 3rd choice "providing a channel over which messages travel" the correct answer ?
And in the 4th choice, which security settings that control the flow of data ?

Thanks

aftereffector

Security settings could be access control lists (ACLs), among other things. Regarding the 3rd option, a channel over which messages travel seems to me to point towards the actual transport layer - copper and fiber cables - as opposed to a "network device".