Read the following passage and questions, then choose the right answer from options, the answer should be one of A, B, C, D.

<passage>:
4.1 OA Policies at Funding Agencies and Universities Authors control the volume and growth of OA. They decide whether to submit their work to OA journals (gold OA), whether to deposit their work in OA repositories (green OA), and how to use their copyrights. But scholarly authors are still largely unfamiliar with their OA options. It’s pointless to appeal to them as a bloc because they don’t act as a bloc. It’s not hard to persuade or even excite them once we catch their attention, but because they are so anarchical, overworked, and preoccupied, it’s hard to catch their attention. Today, more than fifty funding agencies and more than one hundred universities have adopted strong OA policies. Each one depends on the primacy of author decisions. One kind of policy, better than nothing, requests or encourages OA. A stronger kind of policy requires OA or makes it the default for new work. These stronger policies are usually called OA Encouragement policies can target green and gold OA equally. By contrast, mandates only make sense for green OA, at least today when OA journals constitute only about one-quarter of peer-reviewed journals. A gold OA mandate would put most peer-reviewed journals off-limits and seriously limit faculty freedom to submit their work to the journals of their choice. This problem doesn’t arise for green OA mandates. Fortunately, this is well understood. There are no gold OA mandates anywhere all OA mandates are green. Unfortunately, however, many people mistakenly believe that all OA is gold OA and therefore mistake proposed green OA mandates for proposed gold OA mandates and raise objections that would only apply to gold OA mandates. But as more academics understand the green/gold distinction, and understand that well-written green OA mandates are compatible with academic freedom, more institutions are adopting green OA mandates, almost always at the initiative of faculty themselves. At universities, there are roughly three approaches to green OA mandates: These require green OA except when the author’s publisher doesn’t allow it. These require deposit in an OA repository as soon as the article is accepted for publication, but they separate the timing of deposit from the timing of OA. If the author’s publisher doesn’t allow OA, then these policies keep the deposited article dark or non-OA. If the publisher allows OA, immediately or after some embargo, then the deposit becomes OA as soon as the permission kicks in. Because most publishers allow OA on some timetable, this method will provide OA to most new work in due time. Many OA policies are crossbreeds rather than pure types, but all the policies I’ve seen are variations on these four themes. Loophole policies and rights-retention policies both offer opt-outs. But loophole policies give the opt-out to publishers and rights-retention policies give it to authors. The difference is significant because many more authors than publishers want OA for research articles. Many institutions adopt loophole policies because they believe a blanket exemption for dissenting publishers is the only way to avoid copyright problems. But that is not true. Deposit policies don’t make works OA until publishers allow OA, and rights-retention policies close the loophole and obtain permission directly from authors at a time when authors are the copyright holders. OA policies from funding agencies are very much like OA policies from universities. They can encourage green and gold OA, or they can require green OA. If they require green OA, they can do so in one of the three ways above. If there’s a difference, it’s that when funders adopt a rights-retention mandate, they typically don’t offer waiver options. On the contrary, the Wellcome Trust and NIH require their grantees to make their work OA through a certain OA repository on a certain timetable and to retain the right to authorize that OA. If a given publisher will not allow grantees to comply with their prior funding agreement, then grantees must look for another publisher. We should never forget that most toll-access journals already allow green OA and that a growing number of high-quality, high-prestige peer-reviewed journal are gold OA. From one point of view, we don’t need OA mandates when authors already plan to publish in one of those journals. But sometimes toll-access journals change their positions on green OA. Sometimes authors don’t get around to making their work green OA even when their journals allow it. And sometimes authors don’t publish in one of those journals. The final rationale for green OA mandates, then, is for institutions to bring about OA for their entire research output, regardless of how publishers might alter their policies, regardless of author inertia, and regardless of the journals in which faculty or grantees choose to publish. Green OA mandates don’t assure OA to the entire research output of a university or funding agency, for the same reason that they don’t require OA without qualification. But implementing them provides OA to a much larger percentage of the research output than was already headed toward OA journals or OA repositories, and does so while leaving authors free to submit their work to the journals of their choice. I’ve only tried to give a rough taxonomy of OA policies and their supporting arguments. For detailed recommendations on OA policy provisions, and specific arguments for them, see my 2009 analysis of policy options for funding agencies and universities. Second, as I’ve frequently argued, successful policies are implemented through expectations, education, incentives, and assistance, not coercion. Third, even the strongest policies—even the no-loophole, no-deference, no-waiver policies at the Wellcome Trust and NIH—make OA a condition on a voluntary contract. No policy anywhere pretends to impose an unconditional OA requirement, and it’s hard to imagine how any policy could even try. (“You must make your work OA even if you don’t work for us or use our funds”?) 4.3 Digression on the Historical Timing of OA Policies Some kinds of strong OA policy that are politically unattainable or unwise today may become attainable and wise in the future. Here are three examples. Today, a gold OA mandate would limit faculty freedom to submit work to the journals of their choice. But that’s because today only about 25 percent of peer-reviewed journals are OA. As this percentage grows, then a gold OA mandate’s encroachment on academic freedom shrinks. At some point even the most zealous defenders of faculty freedom may decide that the encroachment is negligible. In principle the encroachment could be zero, though of course when the encroachment is zero, and gold OA mandates are harmless, then gold OA mandates would also be unnecessary. It’s understandable that green gratis mandates are spreading faster than green libre mandates, that green mandates in general are spreading faster than gold mandates, and that rights-retention policies with waiver options are spreading faster than rights-retention policies without waivers. However, there is modest growth on one of these fronts: green libre mandates. As researchers become more familiar with OA, as more institutions adopt OA policies, as more new literature is covered by strong OA policies, as more toll-access journals convert to OA, as more toll-access journals accommodate OA mandates without converting, and even as more OA journals shift from gratis to libre, institutions will be able strengthen their OA policies without increasing publisher-controlled rejection rates or author-controlled waiver rates. They should watch the shifting balance of power and seize opportunities to strengthen their policies.

<question>:
When concerning green OA and gold OA,

<options>:
A there are many areas that remain unclear, thus causing policy-making to be difficult unless a greater understanding of their distinctions is garnered.
B all OA mandates are gold, but this is often misconstrued.
C mandates for gold OA are the only ones that make sense.
D there is really no difference.

<answer>:

A