Are you a volcano lover? Here is a list of some of the world's most beautiful volcanoes that our travel agency can offer you to visit. Don't miss them! Mount Mayon, the Philippines Located about 450 km southeast of Manila on the island of Luzon, Mount Mayon is the most active volcano in the Philippines; a September 2014 eruption forced thousands to flee the area. Those who hike the volcano are rewarded with views of the towns in the Albay province and the Pacific Ocean. But even those who prefer the view from a distance have a historical good point at the Cagsawa Ruins, once an 18th Century Franciscan church that was destroyed by an 1814 eruption. Kilauea and Marina Kea, Hawaii Hawaii's volcanoes are known for their active eruptions and extraordinary scenes. Mauna Kea is around one million years old, while Kilauea is the youngest volcano in Hawaii and has been erupting continuously since 1983. The lava falls straight into the sea, creating fantastic forms of black rocks and smoke clouds. Mount Kelimutu, Indonesia Kelimutu's three mysterious crater lakes attract both scientists and tourists to the island of Flores in Indonesia's East Nusa Tenggara province. One is emerald green  , another dark red, and the third pitch black. Scientists say the lakes take on such colors because the volcanic gases met the lakes' minerals centuries ago. The colors of Kelimutu's three mysterious crater lakes are due to  _  .
water pollution different environments chemical reaction different temperatures
Question: Are you a volcano lover? Here is a list of some of the world's most beautiful volcanoes that our travel agency can offer you to visit. Don't miss them! Mount Mayon, the Philippines Located about 450 km southeast of Manila on the island of Luzon, Mount Mayon is the most active volcano in the Philippines; a September 2014 eruption forced thousands to flee the area. Those who hike the volcano are rewarded with views of the towns in the Albay province and the Pacific Ocean. But even those who prefer the view from a distance have a historical good point at the Cagsawa Ruins, once an 18th Century Franciscan church that was destroyed by an 1814 eruption. Kilauea and Marina Kea, Hawaii Hawaii's volcanoes are known for their active eruptions and extraordinary scenes. Mauna Kea is around one million years old, while Kilauea is the youngest volcano in Hawaii and has been erupting continuously since 1983. The lava falls straight into the sea, creating fantastic forms of black rocks and smoke clouds. Mount Kelimutu, Indonesia Kelimutu's three mysterious crater lakes attract both scientists and tourists to the island of Flores in Indonesia's East Nusa Tenggara province. One is emerald green  , another dark red, and the third pitch black. Scientists say the lakes take on such colors because the volcanic gases met the lakes' minerals centuries ago. The colors of Kelimutu's three mysterious crater lakes are due to  _  .
A. water pollution
B. different environments
C. chemical reaction
D. different temperatures
Answer: