Usually under ground springs, or sometimes hollowed earth beneath solid earth where the water pools.
The answer is letter A. evolution always improves organisms. Darwin did not state this idea because he observed that even if evolution happened to species, there were some species that failed to adopt on the new environment. The other choices are his ideas of natural selection which states that an organism can survive if it has heritable traits that can adopt with the environment.
Answer:
Adaptations develop from variations within a population and help organisms to survive in their given environment. Changes in populations accumulate over time; this is called evolution. The fossil record shows us that present-day life forms evolved from earlier different life forms.