An index register that is automatically incremented or decremented with each use is

The correct answer is A. Auto index.

An auto index register is a register that is automatically incremented or decremented with each use. This is useful for performing loops and other operations that require a counter.

B. Asynchronous is a term used to describe events that happen at different times, without any regular pattern.
C. An assembler is a program that converts assembly language into machine code.
D. A compiler is a program that converts high-level language into machine code.
E. None of the above is a type of register.