The power of theories lies in their ability to:
Capture the complexity of human nature by the richness of the operational definitions associated with the variables
Prove conclusively that relationships exist among the phenomena studied
Minimize the number of words required to explain phenomena and thereby eliminate semantic problems
Articulate the nature of the relationships among phenomena

D). Articulate the nature of the relationships among phenomena.

Explanation:

A theory is demonstrated as the formal statement that aims to describe or elucidate a specific process or idea on the basis of general principles.

As per the question, the central power of theories prevails in their ability to 'articulate the nature of the relationships among phenomena' on the grounds of general laws and principles rationally. These acts to provide an understanding of these relationships and acts authentic supporting evidence to substantiate a particular claim or reach a conclusion regarding these phenomena. It also assists in evaluating as well as extending the present knowledge along with providing the explanation and understanding. Therefore, option D is the correct answer.

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