The correct answer is option 2, the Pacific Ocean. Active volcanoes are found in various locations around the world, but a significant number of them are located in the Pacific Ocean region. This area is known as the Pacific Ring of Fire, which is a major area in the basin of the Pacific Ocean where a large number of earthquakes and volcanic eruptions occur. It is a result of plate tectonics where several tectonic plates meet, causing intense volcanic activity. The Pacific Ring of Fire includes countries such as Japan, the Philippines, Indonesia, and many others, which are known for their active volcanoes. While volcanoes can also be found in other oceans, the Pacific Ocean has the highest concentration of active volcanoes.