Question

1. on vacation at a lake, sairas mom sees an interesting - looking rock formation. saira just learned about rocks in geology class and tells her mom that the formation is made of gneiss, a type of metamorphic rock. how did this metamorphic rock form?

a rocks dont form; they stay as they are.
b it melted and cooled.
c it broke into sediment and then compacted.
d it was heated and put under pressure.

Explanation:

Metamorphic rocks form when existing rocks are subjected to high - heat and high - pressure conditions, which cause physical and chemical changes. Option a is incorrect as rocks do change and form through various geological processes. Option b describes the formation of igneous rocks (melted and cooled). Option c describes the formation of sedimentary rocks (breaking into sediment and compaction). Gneiss, a metamorphic rock, forms due to heat and pressure.

Answer:

D. It was heated and put under pressure