Here are the answers to your questions: 1) B) Photosynthesis Photosynthesis is the process by which green plants and some other organisms use sunlight to synthesize foods with the help of chlorophyll. 2) B) Iris The iris is the colored part of the eye that controls the size of the pupil, thereby regulating the amount of light that reaches the retina. 3) D) Skin The skin is the largest organ of the human body, covering the entire exterior and protecting it from the environment. 4) A) Darwin Charles Darwin is widely known for his contributions to the science of evolution, particularly his theory of natural selection. 5) A) Digestion Digestion is the process of breaking down food into smaller molecules that can be absorbed and utilized by the body. 6) B) Chloroplast Chloroplasts are organelles found in plant cells and other eukaryotic organisms that conduct photosynthesis, containing the pigment chlorophyll. 7) A) Cells Cells are the basic structural, functional, and biological units of all known organisms, often referred to as the "building blocks of life." 8) B) Kidney The kidneys are a pair of organs that filter waste products and excess water from the blood, producing urine. 9) A) Adaptation Adaptation is the process by which organisms adjust to their environment to improve their chances of survival and reproduction. What's next?