D. high and low levels of silica in the different type of lava.
Explanation:
The volcanoes have different types of explosions. Some tend to be highly explosive, some less explosive, some don't have explosions at all, while some have combinations of different eruptions. The reason for this diversity in the eruption types is mostly the composition of the magma, or rather how high is the silica content in it.
Basically, the higher the silica level in the magma the higher the explosiveness, and the lower the silica level the lower the chances of explosiveness. This is the case because the higher amount of silica makes the magma thicker, so the gasses are trapped and they explode, while when the lower silica content makes the magma less thick, so the gasses are not trapped and explosions are lacking.
Answer:
The crust because is the thinnest layer
A few major cities located on 38 degrees north latitude:
Niigata, Japan
Seoul, South Korea
Shijiazhuang, China
Taiyuan, China
İzmir, Turkey
Athens, Greece
Palermo, Italy
Lisbon, Portugal
Washington D.C., USA
St. Louis, Missouri, USA
Sacramento, USA
