A pipette is a thin/narrow glass tube that is used to transfer liquids. A spatula is a steel utensils used to scrape, transfer, and apply powders and pastes. A test tube is a glass or plastic tube that is used for holding, mixing, and heating liquid chemicals. A graduated cylinder is a skinny long cylinder used for measuring volumes. So the instrument that would best suitable for holding a liquid while heating it over a flame is a test tube. so the answer is C.