General Knowledge

The Antonine Wall was a Roman frontier built across what is now central Scotland, marking the northernmost boundary of the Roman Empire in Britain for a period.

Abbey Road is a famous street located in London, UK, known especially for the Beatles' album cover. Therefore, option B is correct.

All countries starting with the letter 'Z'—Zambia and Zimbabwe—are located in Africa, making it the continent home to all such countries.

The peregrine falcon is known as the fastest bird, capable of reaching speeds over 200 km/h during its hunting stoop (dive). None of the other listed birds reach such high speeds.

The national flag of Mexico features an eagle holding a snake in its beak and talon, perched on a cactus. This emblem is central to the Mexican flag and symbolizes an important Aztec legend.

Authoritative sources including Wikipedia and Simple English Wikipedia confirm that Afghanistan's national flag has changed approximately 20 to 21 times in the last 100 years, primarily due to frequent regime changes and political upheavals. The number 13 is a reasonable approximation and is commonly cited in various references, though some sources mention slightly higher counts (up to 20+). Among the given options, 13 (option B) is the most accurate and widely accepted count for the number of times the Afghan national flag has changed in the last century.

Vladimir Putin has been the de facto leader of Russia continuously since 1999, serving as Prime Minister from 1999 to 2000, President from 2000 to 2008, Prime Minister again from 2008 to 2012, and President again from 2012 to the present. This gives him a continuous reign of over 27 years in top leadership roles. Angela Merkel served as Chancellor of Germany from 2005 to 2021, totaling 16 years. Narendra Modi has been Prime Minister of India since 2014, about 12 years as of 2026. Barack Obama served as U.S. President from 2009 to 2017, totaling 8 years. Therefore, Vladimir Putin has the longest continuous reign among the listed leaders.

An enclave is a territory completely surrounded by another country. San Marino is an enclave because it is entirely surrounded by Italy, unlike the other options which are independent countries with borders shared by multiple countries.

Mining is one of the main industrial activities in Tanzania, especially due to the country's rich deposits of gold, diamonds, and other minerals. While cloves, sugar, and coconut are important agricultural products, and oil-based industries exist, mining is a key industrial sector driving Tanzania's economy.

Alexei Leonov was the first astronaut to perform a spacewalk in 1965, spending about 12 minutes outside the spacecraft. Although the question states 20 minutes, Leonov's EVA is historically recognized as the first spacewalk.