In February 2015, or the first time, as trial of driverless car was conducted simultaneously in four cities of:

The correct answer is D (Great Britain). In February 2015 the UK government announced a state-backed programme to test driverless cars on public roads in four cities: Bristol, Coventry, Greenwich (London) and Milton Keynes. It was a coordinated, simultaneous trial across several cities, which is what the question is testing.

Why the others are wrong:

• A (U.S.A.): Google and some carmakers tested autonomous vehicles in individual states such as California and Nevada. That was not a four-city government trial announced that month.
• B (Japan): Japan's autonomous driving work in this period was mainly research and later pilot projects linked to the 2020 Tokyo Olympics.
• C (Germany): Germany had notable tests, such as Daimler's Bertha Benz long-distance drive in 2013, but that was a single route demonstration, not a four-city trial.

Core concept: autonomous vehicles and the testbed approach to emerging technology. For Mains, this links to GS-III on science and technology and to policy issues like liability, employment and road safety.

Trap: candidates pick USA because Google's self-driving programme is the best-known example. The question points to a government-led simultaneous trial in four cities, which is the UK.