The correct answer is:
A. II, III, IV, V
These options highlight the key reasons for citing sources: avoiding plagiarism, providing evidence and support for arguments, helping readers locate original sources, and demonstrating depth of research. Option I is not relevant, as simply including many citations does not necessarily enhance the quality of the paper. Option VI, while demonstrating proficiency in citation styles can be important, is not a primary reason for citing sources in an academic context.