The answer is D. Because the bird has to be noticed and the brighter the feathers the more likely the chance to be noticed.
Hippocampal neurogenesis<span> is impacted by environmental factors such as age, excercise, stress and anti-depressant use.</span>
The answer is B. When diatoms die and fall off the ocean column to the ocean floor, they become part of sediments over time. When they are mined and exposed, they turn to a diatomite. Diatomaceous earth is significant as a pest repellant because of its hygroscopic property and has very abrasive particle hence it absorbs the water-protective fats and oils from the outermost layer of insects.
The muscular system allows for movement within the body, for example, during digestion or urination. Smooth muscles in the gastrointestinal or GI tract control digestion. The GI tract stretches from the mouth to the anus. Food moves through the digestive system with a wave-like motion called peristalsis.