Answer:
B. Human activities and natural events can damage the environment.,
Explanation:
Human activities are those activities carried out by a human being. The environment is being degraded daily as a result of the activities of man as well as natural occurrences e.g earthquake, tsunami, wild fire etc.
Human activities also called anthropogenic activities that damage the environment include sewage pollution, burning of fossil fuels, oil spillage etc. Hence, according to this question, human activities and natural events can damage the environment.
Natural selection is the process by which individuals with characteristics that are advantageous for reproduction in a specific environment leave more offspring in the next generation, thereby increasing the proportion of their genes in the population gene pool over time. Natural selection is the principal mechanism of evolutionary change, and is the most important idea in all biology. Natural selection, the unifying concept of life, was first proposed by Charles Darwin, and represents his single greatest contribution to science.
Natural selection occurs in any reproducing population faced with a changing or variable environment. The environment includes not only physical factors such as climate or terrain, but also living factors such as predators, prey, and other members of a population.
Mechanism of Natural Selection
The mechanism of natural selection depends on several phenomena:
• Heredity: Offspring inherit their traits from their parents, in the form of genes.
• Heritable individual variation: Members of a population have slight differences among them, whether in height, eyesight acuity, beak shape, rate of egg production, or other traits that may affect survival and reproduction. If a trait has a genetic basis, it can be passed on to offspring.
• Overproduction of offspring: In any given generation, populations tend to create more progeny than can survive to reproductive age.
• Competition for resources: Because of excess population, individuals must compete for food, nesting sites, mates, or other resources that affect their ability to successfully reproduce.
Given all these factors, natural selection unavoidably occurs. Those members of a population that reproduce the most will, by definition, leave more offspring for the next generation. These offspring inherit their parents' traits, and are therefore also likely to succeed in competition for resources (assuming the environment continues to pose the same challenges as those faced by parents). Over several generations, the proportion of offspring in a population that are descended from the successful ancestor

Uloborid spider eggs and spiderlings. In any given generation, populations tend to create more offspring than can survive to reproductive age.
increases, and traits that made the ancestor successful therefore also increase in frequency. Natural selection leads to adaptation, in which an organism's traits conform to the environment's conditions for existence.
Answer:
A blue moon is an additional full moon that appears in a subdivision of a year: either the third of four full moons in a season, or a second full moon in a month of the common calendar
Explanation:
The Moon can turn blue when there’s a certain amount of dust or pollution in the air. The extra dust scatters blue light, making the Moon appear more blue.
Answer:
D. Spinal nerves have mixed motor and sensory function.
Explanation:
spinal's nerves are mixed nerves, which means that they carry sensory and motor information. They carry sensory information to the central nervous system to give a motor answer that will travel through the spinal nerves to specific muscles. The White matter, which is peripheral in the spinal cord, contains axons while the gray matter, which is central in the spinal cord, contains cell bodies.
The answer is <span>2 can be made by the animal's body from other substances.
Both essential and nonessential amino acids have essential roles in the organism. Nonessential amino acids got their name because they are not an essential part of the diet. The main difference between these two groups of amino acid is that essential amino acids cannot be made by the animal's body and must be ingested in the diet unlike the nonessential amino acid which can be made by the animal's body.</span>