What is the primary role of a switch in a network?

The primary role of a switch in a network is to connect several devices and share resources. A switch operates at the data link layer of the OSI model and is designed to facilitate communication between multiple devices, such as computers, printers, and servers, that are connected to the same local area network (LAN). It does this by receiving data packets from one device and forwarding them to the appropriate destination device based on MAC addresses.

By enabling direct communication between devices, switches help improve the efficiency of data transmission within the network. They can also create separate collision domains for each connection, which reduces the likelihood of data collisions and enhances overall network performance.

In contrast, providing internet access pertains to the role of routers, which connect different networks and direct traffic between them, while security of data in transit often involves encryption protocols rather than the primary function of a switch. Additionally, managing internet traffic flow is more closely associated with routers and other networking devices like firewalls that handle data from various networks rather than just local communication. Therefore, option A encompasses the essential and primary function of a switch, which is to facilitate communication and resource sharing among multiple connected devices.