Beyond the answers - interesting background to this quiz

A belt of dry land on the edge of the desert

The Sahel is a semi-arid band of land that runs across Africa just south of the Sahara, stretching from the Atlantic coast to the Red Sea. Mauritania sits within it, along with countries such as Mali, Niger and Chad. The region is known for its fragile rainfall patterns, where a single dry season can reshape the lives of farmers and herders.

One city, two names in everyday speech

Oslo has been Norway's capital for centuries, though it spent a long period known as Christiania, a name given in the 17th century. The city reverted to Oslo in 1925. Reykjavík and Stockholm, the two distractors here, are the capitals of Iceland and Sweden respectively, which makes the Nordic capitals a classic source of quiz confusion.

A comedy that still works on stage

Much Ado About Nothing is one of Shakespeare's best-loved comedies, built around the sparring lovers Benedick and Beatrice and a plot full of mistaken identity. Its title plays on the old meaning of "nothing", which could also suggest gossip or rumour. The play remains a favourite for open-air theatre because so much of its humour depends on overheard conversations.

Radar and the race to see the invisible

Radar, which uses radio waves to detect objects and measure their distance, was developed intensively during the 1930s and became a decisive tool in World War II. Britain built a chain of coastal radar stations that helped direct fighter planes during the Battle of Britain. It was especially valuable at night and in bad weather, when the human eye could do very little.

Orwell's bleak warning about surveillance

Winston Smith is the protagonist of George Orwell's 1984, a novel set in a totalitarian state where citizens are watched by the ruling Party. The book gave English several enduring phrases, including "Big Brother" and "doublethink". Brave New World and Fahrenheit 451, the other options, are also dystopian novels, which is why they fit so neatly as decoys.