Final answer:
The Open method does not require authentication, unlike PSK and Enterprise method for securing Wi-Fi networks. The Initialization method is not directly relevant to Wi-Fi authentication methods.
Step-by-step explanation:
The option that does not require authentication is the Open method.
In network security, particularly with Wi-Fi networks, different methods are utilised to authenticate users who want to gain access. Options like Pre-shared Key (PSK) and Enterprise method require a user to provide credentials to connect to the network.
The Open method, on the other hand, allows any device to connect without the need for any credentials. It is essential to use authenticated methods for securing networks as the Open method exposes the network to potential security risks. The Initialization method does not directly relate to the authentication methods used for securing Wi-Fi networks.