In the TCP/IP model, what layer is responsible for the movement of data packets using protocols like IP and ARP?

The correct answer is the Internet layer, which is sometimes used interchangeably with the term "Network layer" in various contexts, particularly within the TCP/IP model. This layer is primarily responsible for the movement of data packets across different networks using protocols like Internet Protocol (IP) and Address Resolution Protocol (ARP).

The Internet layer handles the routing of packets, ensuring they reach their designated destination from the source, even if they traverse multiple network paths. It encapsulates packets into datagrams, adds necessary headers (containing information like source and destination IP addresses), and manages the addressing and delivery process.

In contrast, the Application layer is focused on user interfaces and end-user services, the Transport layer ensures the complete transmission of data segments, handling error detection, correction, and flow control. While the Network layer is a part of the broader TCP/IP model, the term "Internet layer" is more specific to the way TCP/IP structures its functionality, particularly in the context of how it enforces routing and address handling protocols dedicated to delivering packets across interconnected networks.