Question

read the paragraph about espionage.
governments use spies to find out secret information about enemies—or even allies—so they can make smart choices during tense times. over the years, spies have used all kinds of clever tricks, from invisible ink and secret codes to modern computers and hidden cameras. of course, spying isnt all glamorous—it brings up tough questions about trust and privacy. for example, when one country secretly listens in on the private conversations of another country that its supposed to be friends with, its hard to tell whether thats smart protection or a serious betrayal.
what is the controlling idea?
○ spying is a clever and exciting activity that helps countries win wars and outsmart their enemies.
○ spying is a necessary but ethically uncertain practice that forces nations to balance security with trust.
○ spying is a dangerous job where secret agents use special tools to gather information.
○ spying is wrong because it breaks trust and should never be used by any country.

Explanation:

The paragraph first mentions that governments use spies for information (necessity). Then it talks about the ethical issues (trust and privacy questions). So the controlling idea should cover both necessity and ethical uncertainty.

Answer:

Spying is a necessary but ethically uncertain practice that forces nations to balance security with trust.