What is the main purpose of the Address Resolution Protocol (ARP)?

The primary function of the Address Resolution Protocol (ARP) is to map IP addresses to their corresponding Media Access Control (MAC) addresses within a local network. This process is essential because while devices on a network communicate using IP addresses, the actual transmission of data over the local area network (LAN) relies on MAC addresses.

When a device wants to communicate with another device over a network, it first needs to determine the MAC address associated with the destination device's IP address. ARP facilitates this by broadcasting a request to all devices on the network, asking for the MAC address that corresponds to the specific IP address in question. The device with the matching IP address will respond, allowing the communication to proceed.

The other choices focus on different networking concepts, such as finding IP addresses or securing networks, which are not the primary function of ARP. Therefore, understanding ARP's role in linking IP addresses to MAC addresses clarifies why it is a fundamental component of network communication and makes the selection of this answer accurate.