The socket module in Python provides access to the BSD socket interface. It is the correct module to use for handling network connections, which allows you to create socket objects necessary for TCP/IP communications, making it possible to check if certain services are running on a port. os is typically used for interacting with the operating system, subprocess is used for running external processes, and struct is used for converting between Python values and C structs represented as Python strings, none of which are directly relevant to creating socket objects for network connections.