The answer would be c.cooling on earth's surface. I think they should have a more simpler answer like: cooling very quickly, but, oh well ;)! Hope this answers ur question, all you guys out there suffering through earth science!
No, a rock with visible layers and no mineral crystals is unlikely to have formed from lava. Such characteristics are typical of sedimentary rocks, which are formed from the accumulation and compaction of sediments. In contrast, igneous rocks that form from lava usually contain visible mineral crystals or a glassy texture due to rapid cooling. Therefore, the rock in question is more likely to be sedimentary rather than igneous.
igneous rocks usally form by cooled magma.
Sedimentary rocks are likely to form when extrusive igneous rock is broken down by weathering. This process involves the erosion and transportation of the weathered rock material, which eventually gets deposited and compacted to form sedimentary rocks.
If igneous rocks are exposed to extreme pressure and heat, they are likely to recrystallize into new igneous rocks. On the other hand, if sedimentary rocks are exposed to extreme pressure and heat, they are likely to metamorphose into metamorphic rocks.
sedimentary
The igneous rock you are describing is likely obsidian. Obsidian is a naturally occurring volcanic glass formed from the rapid cooling of molten lava. Its smooth, glassy texture and black color make it a popular material for decorative items and tools.
The rock you are describing is likely obsidian. Obsidian is a naturally occurring volcanic glass formed during rapid cooling of lava. It is usually black in color and has a smooth, glassy texture.
Glassy igneous rocks cool the fastest. The most likely had more nucleation. Pegmatic cooled the slowest, which is why its crystals are larger than 1 cm. Phaneritic is the next slowest in cooling. Porphyritic has slow then rapid cooling, while aphanitic igneous rocks also have rapid cooling.
igneous rocks usally form by cooled magma.
Sedimentary rocks are likely to form when extrusive igneous rock is broken down by weathering. This process involves the erosion and transportation of the weathered rock material, which eventually gets deposited and compacted to form sedimentary rocks.
Igneous.
Igneous rock
study island cheater! : The igneous rock will be weathered and form sedimentary rock.
If igneous rocks are exposed to extreme pressure and heat, they are likely to recrystallize into new igneous rocks. On the other hand, if sedimentary rocks are exposed to extreme pressure and heat, they are likely to metamorphose into metamorphic rocks.
sedimentary
It is most likely intrusive
The mineral you are describing is likely quartz. Quartz has a glassy luster and can be found in clear or milky white varieties. It is a common mineral that is often used in jewelry and as a component of many rocks.