Read this excerpt:
in fulfillment of this purpose we will not be intimidated by
the threats of dictators that they will regard as a breach of
international law or as an act of war our aid to the
democracies which dare to resist their aggression. such
aid is not an act of war, even if a dictator should
unilaterally proclaim it so to be.
-- franklin d. roosevelt, "four freedoms speech: annual
message to congress on the state of the union," january
6, 1941
which phrase best states the theme of this passage from roosevelt's four
freedoms speech?

B: International law versus an act of war

Explanation:

The main focus of this passage from Franklin D. Roosevelt's speech is to make it clear to the world that aiding allied democracies against threats from dictators is not a breach of international law, neither is it an act of war. And that The USA will not be intimidated by dictators even if they consider this aid an act of war, or breach of international law.

So, considering the main focus and topic of the passage the theme of this passage is international law versus an act of war.

There is just a minute hint to use of force (proper or improper), and peace and enemy's aggression. so these can't be the regarded as the passage's theme. Similarly, although there is mention of dictators, yet it is not stressed.

in ray bradbury's short story "a sound of thunder", mr. eckels's fearfulness leads to drastic consequences for the rest of the world.

in the story, mr. eckels, who is a hunter, hires a time travel company to travel to the age of dinosaurs. although he is excited for the hunting expedition at the beginning, when they reach there and mr. eckels sees the tyrannosaurus, he feels frightened. as he is afraid of the tyrannosaurus, he steps off the path although he has been warned not to do it. by stepping off the path, the entire course of the future is affected: mr. eckart alters the future by stepping on a butterfly, which causes a new man to be elected president in the future. in that way, it is mr. eckart's fearfulness what triggers 'the butterfly effect' and what leads to drastic consequences for the rest of the world.