Choice "D" is correct. The regulations allow the use of a "red herring" prospectus in certain circumstances. A "red herring" prospectus may be missing certain information that is not yet available.
Choice "c" is incorrect. There is no provision for an unaudited prospectus.
Choice "a" is incorrect. There is no provision for a qualified prospectus.
Choice "b" is incorrect. "Blue sky" is the general name given to state securities laws, derived from the idea that without the laws, people could be lured into investing in the "blue sky."