The correct answer is: Both (A) and (R) are correct, but (R) is not the correct explanation of (A).
Management is a continuous process involving the integration of all functions. This means that managers must constantly be planning, organizing, and controlling their work. However, the order in which these functions are performed may vary depending on the situation. For example, a manager may need to control a situation before they can effectively plan for it.
The reason given in the question is not the correct explanation of the assertion. The reason states that management first plans, then organizes, and finally performs the function of controlling. However, this is not always the case. As mentioned above, the order in which these functions are performed may vary depending on the situation.
In conclusion, both (A) and (R) are correct, but (R) is not the correct explanation of (A).