C Because Limestones are Formed In shells and corals so it is subjected to intense heat and any times of pressure
Hope this helps :)
An internal skeleton is used to help an organism hold its body up and keep from falling, while a stem stores nutrients, and produces new living tissue, and transports fluids.
A. Fine Focus.
B. Nucleus, Cytoplasm, and membrane
C. 30 Micrometer.
Erythrocytes are well known to have no nucleus but in fact, they lack most organelles such as the Golgi apparatus endoplasmic reticulum and mitochondria. Hair consists of two parts the root and the hair shaft. The root is the part of the living hair located in the middle layer of the skin the dermis.
Epidermal root cells in some plants produce root hairs and tubular growths that increase the surface area of the root. Unlike other cells in the body, red blood cells do not have a nucleus. This habit dates back to when mammals began to evolve. Other vertebrates such as fish reptiles, and birds have erythrocytes that contain dormant nuclei. To allow red blood cells to carry an increased load of oxygen cells evolved to function without a nucleus and other associated organelles.
Learn more about Cell Types here:-brainly.com/question/342784
#SPJ1