Comparing the different types of volcanoes (e.g., Hawaiian volcanoes and the Mt. St. Helens volcano), why does the difference in the composition of the magma that fed these volcanoes determine the type of volcano? A. Mt. St. Helens was explosive because the magma was less viscous (less "sticky") and mafic.B. Hawaiian volcanoes are the result of subduction.C. Hawaiian volcanoes explode.D. Mt. St. Helens was explosive because the magma was more viscous (more "sticky") and felsic.