While studies indicate that university professors spend much of their time engaged in personal research not clearly related to teaching, it is unlikely that additional financial compensation for, say, a larger course load or longer office hours would be the most effective of various possible means of shifting the focus of their activities; this would be the best means only if their motivation to educate were no more than a mechanical response to the prospect of more money, which surely is not the case. Which one of the following most accurately expresses the main conclusion of the argument? ['The research conducted by most professors should be clearly related to their teaching activities.', 'Monetary incentives would probably be less effective than some other ways that professors might be induced to focus more on teaching activities.', 'Increased financial compensation would be a somewhat effective way to motivate professors to focus their activities on teaching.', 'Effective incentives to encourage larger course loads or longer office hours would shift the focus of professors toward teaching.']