Question: Which of the following statements concerning magma generation and behavior, or volcanic processes, is FALSE? Need Assignment Help? Group of answer choices Deeper in the mantle, the greatly increased pressure forces mantle rock to remain solid despite the high temperatures found at those depths. Although the outer core of the Earth is liquid, it is composed of liquid metals rather than magma, so magma does not originate in the core. Apart from obsidian (volcanic glass), most igneous rocks are composed of mineral crystals, even if those crystals are microscopic in size. Magmas below the Earth's surface cool more slowly than those that erupt at the surface, so they have more time for larger crystals to form. The magma for most volcanic eruptions originates in a layer of molten rock that underlies the Earth's crust and forms the top of the mantle.