Choice "A" is correct. Under Regulation D, the SEC must be notified within 15 days after the first sale of the offering.
Choice "d" is incorrect. Rule 505 offerings can be sold to an unlimited number of accredited investors, but there can be no more than 35 unaccredited investors.
Choice "b" is incorrect. General solicitation generally is prohibited under Regulation D.
Choice "c" is incorrect. Under Rule 505, a balance sheet is required if there are unaccredited investors, but a prospectus is not required.
