About 78% of the planet Earth is composed of ———rocks. A. Igneous B. Sedimentary C. Metamorphic D. Stratigraphy 0 0 votes Article Rating Subscribe Login Notify of new follow-up comments new replies to my comments Label {} [+] Name* Email* Label {} [+] Name* Email* 0 Comments Oldest Newest Most Voted Inline Feedbacks View all comments