"But no person who was, on January 1, 1866, or at any time prior thereto, entitled to vote under any form of government, or who at that time resided in some foreign nation, and no lineal descendant of such person, shall be denied the right to register and vote because of his inability to so read and write sections of such constitution."

We have difficulty in finding words to more clearly demonstrate the conviction we entertain that this standard has the characteristics which the Government attributes to it than does the mere statement of the text. It is true it contains no express words of an exclusion from the standard which it establishes of any person on account of race, color, or previous condition of servitude prohibited by the Fifteenth Amendment, but the standard itself inherently brings that result into existence since it is based purely upon a period of time before the enactment of the Fifteenth Amendment and makes that period the controlling and dominant test of the right of suffrage."
—Guinn v. United States, 1915

Question
Use the passage to answer the question.
Which voting practice did this Supreme Court decision address?

(1 point)
Responses

grandfather clause
grandfather clause

poll tax
poll tax

literacy test
literacy test

Jim Crow laws
Jim Crow laws

grandfather clause