Which of the following are standard file pointers in C?

The standard file pointers in C are associated with the standard input and output streams used for interacting with the user and the operating system. Specifically, 'stdin' refers to the standard input stream, which is typically the keyboard, 'stdout' is the standard output stream, typically the console or terminal where the program writes output, and 'stderr' is the standard error stream used for outputting error messages, often displayed on the same terminal.

These file pointers are defined in the C library and are essential for performing input and output operations efficiently. For example, when using functions like 'fscanf' or 'fprintf', passing these standard file streams allows the program to read from or write to the appropriate locations without needing to specify file descriptors explicitly.

The other options listed do not represent standard file pointers. The first option lists data types, which are not file pointers. The third option discusses functions for formatted output and input, but again, these do not represent file pointers. The fourth option refers to general operations that relate more closely to file handling but lacks the specificity of representing the standard pointers defined in C. Thus, the choice of standard file pointers is accurately identified as 'stderr', 'stdin', and 'stdout'.