Answer:
D)clues about the past climate of Earth
Explanation:
The fossil record certainly has gaps, mostly because the conditions required to create fossils have been rare ever since life began on Earth. A very small percentage of animals that have lived and died ever became fossils. Thus, many pieces of the puzzle are missing; some will never be found.
4-Growth, maintenance, balance fluids, maintain proper hp
2-Actin, collagen
Lipids are are inorganic compound that are poorly soluble in water, that consists of fat and oil. All lipids contain carbon, hydrogen, and oxygen. Some of them also contain nitrogen and phosphorus. The four main classes of lipids are fats, waxes, sterols, and phospholipids. The two parts make up lipids are glycerol and fatty acid.