The third one,
Autotrophs use a process called photosynthesis to make their food. In photosynthesis, autotrophs use energy from the sun to convert water from the soil and carbon dioxide from the air into a nutrient called glucose. Glucose is a type of sugar. The glucose gives plants energy. Plants also use glucose to make cellulose, a substance they use to grow and build cell walls.
By studying the fossil record we can tell how long life has existed on Earth, and how different plants and animals are related to each other. Often we can work out how and where they lived, and use this information to find out about ancient environments.
Male Birds are usually the colorful birds to attract mates while females are camouflaged to protect their eggs/hatchlings. Ground birds need to be camouflaged because they are easy prey and they have their nests on the ground.