Answer:
B. Allow only the smartest, most qualified citizens to vote on the government.
Explanation:
As the United States is a democracy, every citizen has the right to vote in spite of its race, color, social class, religion or any other fact.
Option A is held in the 15th Amendment ratified in 1870.
Option C is the 26th Amendment ratified in 1971.
And finally, option D is the 12th Amendment ratified in 1804.
I hope this answer helps you.