On which OSI layers does a NIC operate, and which are examples of protocols it uses for communication?

• A. Physical Layer (Layer 1) and Data Link Layer (Layer 2); Ethernet protocol; Wi-Fi protocol
• B. Network Layer (Layer 3) and Transport Layer (Layer 4); IP protocol; TCP protocol
• C. Presentation Layer (Layer 6) and Session Layer (Layer 5); TLS; SSL
• D. Application Layer (Layer 7) and Physical Layer (Layer 1); HTTP; ARP

Answer: (A)

A NIC operates at the lowest layers of the OSI model: the Physical layer, which handles the actual signaling on the medium (bits being transmitted as electrical, optical, or radio signals), and the Data Link layer, which frames data, adds MAC addresses, and performs basic error detection. Because of this, the protocols it uses for communication are those defined for the link layer, with Ethernet for wired connections and Wi‑Fi (IEEE 802.11) for wireless. Higher-layer protocols like IP, TCP, TLS, or HTTP live in upper layers and are handled by the host’s networking stack, not by the NIC itself.