The correct answer is Option 3: Japan.

In the year 2007, an earthquake did occur, but it did not result in massive radioactive water leakage in the largest nuclear plant in the world. However, a significant incident did take place in Japan that matches the given description. It was the Fukushima nuclear disaster, which occurred on March 11, 2011.

On that day, a powerful undersea megathrust earthquake, measuring 9.0 on the Richter scale, struck off the eastern coast of Japan. The earthquake triggered a massive tsunami that inundated the Fukushima Daiichi Nuclear Power Plant, located in Fukushima Prefecture, Japan. The plant experienced a loss of power, leading to a failure of the cooling systems for the reactors.

As a result, a series of explosions and meltdowns occurred at the nuclear plant, causing the release of radioactive materials into the environment. The primary source of leakage was contaminated water that had accumulated in the reactor buildings and the underground tunnels of the plant. This radioactive water seeped into the nearby Pacific Ocean, resulting in a significant environmental and public health crisis.

The Fukushima disaster had a profound impact on Japan and the international community. It led to the evacuation of thousands of people from the affected areas, contamination of agricultural land, and increased concerns about the safety of nuclear power. Efforts to contain and mitigate the damage from the disaster have been ongoing since 2011.

To summarize, in the year 2007, there was no earthquake-related massive radioactive water leakage in the largest nuclear plant in the world. However, the Fukushima nuclear disaster, which occurred in Japan in 2011 due to an earthquake and subsequent tsunami, matches the given description.