Ahubis aphysical layer (Layer 1)networking device used to connect multiple Ethernet devices in a network. Unlike switches or routers, hubs donot inspect or process frame headers. Instead, they perform a simple task:

Receive a signal (electrical or optical) on one port

Replicate that signal identically to all other ports

This means the hubdoes not examine Layer 2 (MAC addresses) or Layer 3 (IP addresses)and doesnot perform intelligent forwarding. It merelybroadcasts all incoming traffic to every other connected device, often resulting inhigh collision domainsand poor efficiency.

Option Adescribes arepeater, not a hub.

Option Cdescribes aswitch(Layer 2 device).

Option Ddescribes arouter(Layer 3 device).

Option Bis correct: A hub does not inspect headers and replicates traffic blindly.