Introduction:
A micro programmed control unit is a type of control unit used in computer systems to execute instructions. It is responsible for fetching instructions from memory, decoding them, and generating control signals to coordinate the operations of other components in the system. There are two main types of control units: hardwired and micro programmed. In this question, we are asked to identify the advantages of a micro programmed control unit.

Advantages of a micro programmed control unit:

1. Facilitates easy implementation of a new instruction: One of the main advantages of a micro programmed control unit is its ability to easily implement new instructions. In a micro programmed control unit, the control logic is stored in microcode, which is a set of microinstructions. These microinstructions can be easily modified or added to, allowing for the implementation of new instructions without the need to change the hardware. This is in contrast to a hardwired control unit, where implementing a new instruction would require physical changes to the hardware. Therefore, a micro programmed control unit provides flexibility and ease of modification, making it suitable for systems that require frequent updates or additions of instructions.

2. Useful when small programs are to be run: Another advantage of a micro programmed control unit is its efficiency when running small programs. Microcode allows for the execution of complex instructions through a sequence of microinstructions, which can be tailored to the specific needs of the instruction. This allows for efficient execution of complex instructions, even in systems with limited resources. In contrast, a hardwired control unit may not be as efficient when executing complex instructions, as it relies on a fixed set of control signals. Therefore, a micro programmed control unit is particularly useful in systems that frequently execute small programs or have limited resources.

Conclusion:

In summary, a micro programmed control unit provides the advantage of easy implementation of new instructions through the use of microcode. It allows for flexibility and ease of modification, making it suitable for systems that require frequent updates or additions of instructions. Additionally, it is efficient when running small programs or operating under limited resources. Therefore, the correct answer to the question is option 'B'.