Select the sentence from the article that suggests that a metamorphic rock was once another type of rock. (A) In geology, pictures of rocks can be used to help you best determine which of the three major types a
particular rock belongs to: igneous, sedimentary or metamorphic.
(B) Metamorphic rock formation occurs when sedimentary or igneous rock becomes changed, or
metamorphosed, by conditions underground.
(C) Most of the thousands of rare minerals known to science occur in metamorphic rock.
(D) Common examples of metamorphic rock include: marble, phyllite and serpentinite.