In his four freedoms speech, roosevelt believes that to attain "freedom from fear" the world must:

a. ban the sale and use of weapons.
b. give weapons to all citizens.
c. agree never to use weapons.
d. reduce the number of weapons.

The answer is D: reduce the number of weapons

 One of the freedoms that president Roosevelt included in his Four Freedoms speech was the freedom from fear, in which he defends the idea that no country  in the world would be able commit and act of physical aggression against any neighbor. And to achieve this position, they should agree with a worl-wide reduction of armaments.