What does 'ISP' stand for?

The correct answer is "Internet Service Provider." An ISP is a company that provides individuals and organizations access to the Internet. ISPs can offer various services, including broadband, dial-up, and wireless connections, as well as additional services such as email accounts, web hosting, and domain registration. The primary role of an ISP is to establish and maintain the infrastructure that allows users to connect to the Internet.

In contrast, the other options represent different concepts that do not accurately define the term 'ISP.' Information Security Protocol refers to methods and standards for securing communications over networks. Internal Software Platform implies a type of software environment used within an organization, which is unrelated to Internet access. Interactive Service Platform could refer to a technology allowing users to interact with services online but does not encapsulate the function of connecting users to the Internet.