What is evolution?
explain it briefly ​

In biology, evolution is the change in the characteristics of a species over several generations and relies on the process of natural selection. ... Evolution relies on there being genetic variation? in a population which affects the physical characteristics (phenotype) of an organism.

hello Here is your answer

Explanation:

Evolution is a process witnessed in living entities wherein gradual changes are observed in the characteristics of species over generations attributed to the process of natural selection. Charles Darwin was the first person who observed the process and formulated the scientific theory of evolution.

It is based on the very fact that all species are related and eventually undergo changes over a period of time. It is also dependant on genetic variation in a population that has an influence on the phenotype of an organism. This change which occurs is usually in a much better and complex form. In response to the environment, an entity becomes more sophisticated over a period of time. It is a biological mechanism driven by natural selection.

Darwin’s theory states that evolution occurs through the process of natural selection. An individual is able to exhibit changes in his phenotype or physical characteristics because of the differences in his genes. It was deduced that those entities with attributes that best suited to their surroundings have more chances to survive, resist diseases, avoid predators and hence to be able to find food. These are the entities that are more likely to pass their genes to the next generation via the biological process of reproduction. On the contrary, entities that are poorly adapted to their surroundings are less likely to reproduce and survive and thus their chances of passing on genes to the next generation are comparatively lower. Hence those who survive and reproduce evolve eventually.

the correct answer is 4) heat and pressure

metamorphic rocks arise from transformation of existing rocks types, in a process called metamorphism. during metamorphism the original rock(prolith) change into metamorphic rock by heating (150-200c) and pressure of more than 1000 bar. the original rock can be sedimentary, igneous, or existing metamorphic rock.