Which of these statements best describes evolution? a. the progression through time from simple to complex organisms. b. a process of change through time. c. evolution causes organisms to develop characteristics they need. d. the progression from complex to simple organisms

The answer is 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 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.