Final answer:
The most dangerous volcanically locations are those with a propensity for explosive eruptions, like in Indonesia, and those near plate boundaries, which can present both volcanic and earthquake hazards. Volcanoes over hot spots can also be dangerous but tend to exhibit less violent eruptions.
Step-by-step explanation:
The most dangerous volcanic location would be areas with a history of explosive eruptions, such as the islands of Sumatra and Java in Indonesia. Indonesia is densely populated and has over 150 active volcanoes, including Krakatoa and Tambora, known for their cataclysmic eruptions. There are different types of volcanic eruptions, and while some volcanoes like those in Hawaii erupt effusively, producing relatively gentle lava flows, others explode violently. The danger lies not only in the eruption itself but also in related hazards such as lahars, pyroclastic flows, and volcanic ash.
Areas above mantle hot spots, like the Hawaiian Islands, generate long chains of volcanoes due to the Earth's plates moving over fixed points of heat in the mantle. These volcanoes can form massive mountains, such as Mauna Kea, which is used for astronomy due to its dormant state. However, living near plate boundaries can pose risks due to both earthquakes and volcanic activity, as seen in the historic disasters along subduction zones.