5. On vacation at a lake, Saira’s 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?

Question

Responses

a
Rocks don’t form; they stay as they are.
Rocks don’t form; they stay as they are.

b
It melted and cooled.
It melted and cooled.

c
It broke into sediment and then compacted.
It broke into sediment and then compacted.

d
It was heated and put under pressure.

Answer 1

The correct response is:

d It was heated and put under pressure.

Gneiss is a type of metamorphic rock that forms from the alteration of pre-existing rocks (either igneous, sedimentary, or other metamorphic rocks) through the processes of heat and pressure.