Which of the Following Statements Pertaining to Tax Law Is

Which of the following statements pertaining to tax law is true?
I.A tax textbook is considered a primary source.
II.Secondary sources help locate and interpret primary sources.
III.Primary sources emanate from the three branches of the federal government.
IV.An article in a law journal written by a former commissioner of the Internal Revenue Service is considered a secondary source of tax law.
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A) Only statement I is correct.
B) Statements I and II are correct.
C) Statements I, II, and III are correct.
D) Statements II, III, and IV are correct.
E) Statements I, II, III, and IV are correct.