Which of the following is not a valid example of a web schema?

The correct answer is "was." In the context of web schema, valid examples are protocols used to transfer data over the internet. "HTTP" (HyperText Transfer Protocol), "FTP" (File Transfer Protocol), and "Gopher" are all established protocols that facilitate communication and data retrieval on the web. These protocols define rules and conventions for transferring various types of data between clients and servers.

"Was," on the other hand, does not represent any recognized or valid web schema utilized for transferring data. It lacks the technical foundation and purpose necessary to be classified as a protocol like HTTP, FTP, or Gopher. Understanding this distinction is crucial in the field of internet technology and communications, as it ensures that one can accurately identify and utilize the correct methods for data exchange.