Consider the following statements:

(i) Address Resolution Protocol (ARP) provides a mapping from an IP address to the corresponding hardware (link-layer) address.

(ii) A single TCP segment from a sender S to a receiver R cannot carry both data from S to R and acknowledgement for a segment from R to S.

Which ONE of the following is CORRECT?

The correct answer/option is: (i) is TRUE and (ii) is FALSE.

Let us analyze each statement step-by-step to understand why this option is correct:

Statement (i): Address Resolution Protocol (ARP) provides a mapping from an IP address to the corresponding hardware (link-layer) address.
This statement is TRUE.
In a local area network (LAN), when a device wants to send an IP datagram to another device on the same physical network, it knows the destination's IP address (Network Layer address). However, data link layer frames require the physical hardware address (MAC address) of the destination to deliver the frame locally. ARP resolves this by mapping the given IPv4 address to its corresponding physical MAC address. Thus, statement (i) is correct.

Statement (ii): A single TCP segment from a sender S to a receiver R cannot carry both data from S to R and acknowledgement for a segment from R to S.
This statement is FALSE.
TCP supports a mechanism known as piggybacking. When a sender S has data to send to receiver R, and at the same time needs to acknowledge a previously received segment from R, it does not need to send two separate segments (one for data and one for the acknowledgement). Instead, it can place the acknowledgement number in the acknowledgement field, set the ACK flag, and include the payload data all within a single TCP segment. This reduces protocol overhead and network traffic. Since a single TCP segment can indeed carry both data and an acknowledgement, statement (ii) is false.