Which type of eukaryotic transcription factors can increase the level of transcription in certain cells in response to signals

Which phrase is most likely to start a description of a scientific theory? “what i have found through my online research is . .” “after much thought, i believe that the best explanation is . .” “based on the observations made and experiments performed over the last fifty years . .” “if sunlight shines on the right side of a plant, then the plant will grow toward the right because . .”

The many stone tools, fragmentary animal bones, and teeth found at gran dolina, spain, indicate that hominids there? a. processed and consumed animals and other hominids. b. did not differ appreciably from earlier asian homo erectus. c. were similar to later homo sapiens. d. none of the above

In general, characteristics that an organism survive and reproduce become more common in a population over time. what mechanism of evolution cause this change?