One of the main feature that distinguish microprocessors from microcomputers is

words are usually larger in microprocessors
words are shorter in microprocessors
microprocessor does not contain I/O devices
exactly the same as the machine cycle time E. None of the above

The correct answer is: C. microprocessor does not contain I/O devices.

A microprocessor is a single integrated circuit that contains all, or most of, the central processing unit (CPU) of a computer or other digital electronic device. Microprocessors contain both combinational logic and sequential digital logic, and operate on numbers and symbols represented in the binary numeral system.

A microcomputer is a small computer that uses a microprocessor as its central processing unit. Microcomputers are typically used for personal or home use, and are often referred to as personal computers (PCs).

The main difference between a microprocessor and a microcomputer is that a microprocessor does not contain I/O devices, while a microcomputer does. I/O devices are devices that allow a computer to communicate with the outside world. Examples of I/O devices include keyboards, mice, monitors, printers, and storage devices.

Microprocessors are typically used in embedded systems, which are systems that are dedicated to a specific task or application. Embedded systems are often found in appliances, automobiles, and industrial equipment.

Microcomputers are typically used for general-purpose computing tasks, such as word processing, spreadsheets, and games.

Here is a brief explanation of each option:

  • Option A: Words are usually larger in microprocessors. This is not true. The size of a word is determined by the architecture of the microprocessor, not by whether it is a microprocessor or a microcomputer.
  • Option B: Words are shorter in microprocessors. This is also not true. The size of a word is determined by the architecture of the microprocessor, not by whether it is a microprocessor or a microcomputer.
  • Option C: Microprocessor does not contain I/O devices. This is the correct answer. Microprocessors do not contain I/O devices, while microcomputers do.
  • Option D: Exactly the same as the machine cycle time. This is not true. The machine cycle time is the time it takes for a microprocessor to complete one instruction. The size of a word is not related to the machine cycle time.
  • Option E: None of the above. This is also not true. The correct answer is Option C.