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MAC : Media Access Control by Macintosh

>>>>>>>>>>>>>>>>>>>>>>> c) Media Access Control 

Media access control or the abbreviation of Apple's Macintosh 

Answer

c) Media Access Control 

A Media Access Control address (MAC address) is a unique identifier assigned to network interfaces for communications on the physical network segment. Logically, MAC addresses are used in the Media Access Control protocol sub-layer of the OSI reference model.

MAC addresses are most often assigned by the manufacturer of a network interface card (NIC) and are stored in its hardware, the card's read-only memory, or some other firmware mechanism. If assigned by the manufacturer, a MAC address usually encodes the manufacturer's registered identification number. It may also be known as an Ethernet hardware address (EHA), hardware address, adapter address, or physical address.

Although intended to be a permanent and globally unique identification, it is possible to change the MAC address on most of today's hardware, an action often referred to as MAC spoofing. Unlike IP address spoofing, where a sender spoofing their address in a request tricks the other party into sending the response elsewhere, in MAC address spoofing, the response is received by the spoofing party. However, MAC address spoofing is limited to the local broadcast domain.

In the IPv4 world, the MAC address of your computers is not propagated or detectable beyond your local network. This means that under normal browser operation (without plugin intervention), the MAC address of any computer positioned behind the router is not sent beyond the router, and so cannot be used to track you over the Internet. However, the router uses it internally in order to identify the local computers.

In IPv6, the bit "host" part of the full bit address is often automatically generated from the MAC address, and hence often is visible to the server one connects to. This means that outsiders may trace the MAC address of your router and your Internet-connected computers. IPv6 gives a public, routable address to every last PC, server, printer or network device (unless the router does NAT processing, which is rare in IPv6).

If private IPv6 address (defined in RFC) is turned on, the exposed identifier is generated as a random number rather than from the MAC. This is the default on many operating systems, but can be turned on and off. For further info see How to avoid exposing my MAC address in IPv6?

In any case, your ISP always knows who you are and can trace anything you do, unless the traffic is encrypted by using a VPN.

Answer of the above question is Media Access Control

Option C Media Access Control ..........

Whether you work in a wired network office or a wireless one, one thing is common for both environments: It takes both network software and hardware (cables, routers, etc.) to transfer data from your computer to another—or from a computer thousands of miles away to yours.

Media Access Control, Also called physical Address, Every network device having MAC Address