Medium
The World Wars
Causes, Turning Points & Treaties
How both wars began, turned and were settled.
Sample question
Start quiz
In which year did the First World War begin?
Codes, Spies and Intelligence
A great deal of both wars was decided by what each side knew, and by what it could make the other believe.
About this topic
Intelligence work is badly served by its popular image. The decisive activity was rarely a lone agent in a trench coat; it was industrial-scale codebreaking, careful traffic analysis, and elaborate deception designed to make an enemy commit forces in the wrong place. These questions cover the machinery, the people and the operations, including the persistent problem that using intelligence can reveal you have it — which sometimes meant not acting on what was known.
Questions & answers
Codes, Spies and Intelligence: all 10 questions and answers
Every question in this quiz is listed below with its correct answer and the reasoning behind it. Play first if you would rather not see the answers — or read through as a study sheet.
Play it insteadShow all answers and explanationsHide answers
-
1The Enigma machine was used principally by which country?
- A Japan
- B Germany Correct
- C Britain
- D The United States
Answer: B. Germany
Why: It was a commercial design adapted for military use, generating a substitution that changed with every keystroke.
-
2British codebreaking during the Second World War was centred where?
- A Bletchley Park Correct
- B The Tower of London
- C Portsmouth
- D Edinburgh Castle
Answer: A. Bletchley Park
Why: At its height it employed thousands, a majority of them women, and the work stayed secret for decades after the war ended.
-
3Alan Turing's major contribution at Bletchley was what?
- A Inventing radar
- B Commanding a codebreaking unit
- C Translating intercepts
- D Designing a machine to accelerate breaking Enigma settings Correct
Answer: D. Designing a machine to accelerate breaking Enigma settings
Why: The bombe tested possible settings mechanically, exploiting predictable phrases likely to appear in a message.
-
4Polish cryptographers contributed what before the war?
- A Nothing, as they had no programme
- B Only diplomatic codes
- C Early breaks into Enigma, shared with Britain and France in 1939 Correct
- D The machine itself
Answer: C. Early breaks into Enigma, shared with Britain and France in 1939
Why: Their work gave Britain a foundation that would have taken far longer to build from nothing.
-
5The Navajo code talkers were used in which theatre?
- A The Atlantic
- B The Pacific Correct
- C North Africa
- D The Eastern Front
Answer: B. The Pacific
Why: The language was unwritten and known to very few outsiders, and a coded vocabulary was layered on top of it.
-
6Operation Mincemeat involved what?
- A Planting false documents on a body to mislead German planners Correct
- B A bombing raid on a codebreaking centre
- C The capture of an Enigma machine
- D A double agent in Berlin
Answer: A. Planting false documents on a body to mislead German planners
Why: The deception aimed to draw defences away from Sicily, and German dispositions suggest it worked.
-
7The Zimmermann Telegram helped bring which country into the First World War?
- A Italy
- B Japan
- C Brazil
- D The United States Correct
Answer: D. The United States
Why: British intelligence intercepted a German proposal to Mexico and had to reveal it without exposing that German codes were being read.
-
8A one-time pad is theoretically unbreakable provided what?
- A The message is short
- B It is written in code words
- C The key is truly random, as long as the message, and never reused Correct
- D It is used only once a day
Answer: C. The key is truly random, as long as the message, and never reused
Why: Reuse destroys the security completely, which is how some Soviet traffic was eventually read in the Venona project.
-
9Using decrypted intelligence carried what risk?
- A Legal prosecution
- B Revealing to the enemy that their code was broken Correct
- C Damaging the machines
- D Slowing communications
Answer: B. Revealing to the enemy that their code was broken
Why: Commanders sometimes had to forgo acting on information, or arrange a plausible alternative source, to protect the secret.
-
10Traffic analysis extracts intelligence from what?
- A Patterns of communication, without reading the contents Correct
- B Only fully decrypted messages
- C Radio interference
- D Weather reports
Answer: A. Patterns of communication, without reading the contents
Why: Volume, timing and who is signalling whom can reveal an impending operation even when the messages remain unreadable.
Frequently asked questions about Codes, Spies and Intelligence
How many questions are in Codes, Spies and Intelligence?
Codes, Spies and Intelligence has 10 questions and takes about 8 minutes to finish. It is rated Hard and sits in our The World Wars category.
How is Codes, Spies and Intelligence scored?
Each of the 10 correct answers adds 10 XP, up to 100 XP for a clean run. Wrong answers cost you nothing, and your full question-by-question review is shown at the end.
Are the answers to Codes, Spies and Intelligence explained?
Yes. All 10 questions carry a written explanation of why the correct answer is right, so the quiz works as a study sheet as well as a test.
Can I replay Codes, Spies and Intelligence?
Yes, as often as you like. The questions and the answer options are reshuffled on each run, and you can use Practice Mistakes afterwards to retry only the ones you missed. No account is needed to play.
QuizKite Quality Guarantee
Every quiz on QuizKite is researched, written and fact-checked by hand against reliable references, with an explanation for each answer. Read our full Editorial Policy to learn more about our content standards.
Keep going
More The World Wars
Medium
The World Wars
Life in the Trenches
No man's land, duckboards, gas and the daily conditions of the Western Front.
Sample question
Start quiz
In trench warfare, what was no man's land?
Medium
The World Wars
What the Wars Left Behind
Reparations, ruined currencies, new borders and the institutions built out of the wreckage.
Sample question
Start quiz
Which body was created after the First World War to prevent future conflicts between states?
Medium
The World Wars
The First World War
Ten questions on the alliances, campaigns and decisions that shaped the war of 1914 to 1918.
Sample question
Start quiz
Germany, Austria-Hungary and the Ottoman Empire fought the war as which grouping?
Medium
The World Wars
The Second World War in Europe
From the pact of August 1939 to the fall of Berlin, ten turning points in the European war.
Sample question
Start quiz
Which agreement of August 1939 committed Germany and the Soviet Union to non-aggression days…
Hard
The World Wars
The War in the Pacific
Carriers, codebreakers and island campaigns across the largest theatre of the Second World War.
Sample question
Start quiz
Which June 1942 battle cost Japan four fleet carriers and reversed the balance in the Pacific?