Dr. Ensing studies the reactions of very young children who are briefly separated from their mothers while in an unfamiliar setting. It is most likely that Dr. Ensing is conducting research on

All of the following are examples of sedimentary rocks except? a) sandstone made of small pieces of sand cemented together b) coquina made of small shells cemented together c) shale made of small silt particles cemented together d) quartzite, or sandstone that has been subject to high pressure and heat over time