Which of the following describes an 'effective teacher' in the context of teaching the principles of electricity?
ASomeone who possesses a Ph.D. in Electrical Engineering and has published numerous research papers.
BSomeone who ensures students strictly adhere to safety protocols and completes the syllabus on time.
CSomeone who prepares students thoroughly for exams by focusing on memorization of formulas and definitions.
DSomeone who is skilled at explaining complex concepts in multiple ways using different analogies and models.