The answer is <span> b. a process of change through time.
Evolution is a process of change through time. It does not result in progress. Natural selection, one of the mechanisms of evolution, can result in progress and </span>cause some organisms to develop characteristics they need. But generally speaking, natural selection is not the only mechanism of evolution. Other evolutionary mechanisms, such as genetic drift, mutations, migration, can in some cases have a harmful outcome.
Because if you take care of your body/organs by exercise and good diet then your bidy will stay healthy without sickness which results in longer life span