Darwin's theory of evolution posits that development is primarily influenced by which factor?

• A. Social environment
• B. Biological influences
• C. Language development
• D. Economic systems

Answer: (B)

Biological influences are the driving factor. Darwin’s theory explains that there is variation in heritable traits within a population, and those traits that improve an organism’s chances of surviving and reproducing tend to become more common over generations. This process—natural selection—depends on biology, because the variations come from genetic differences. Social environment, language development, and economic systems shape behavior and human society, but they do not constitute the primary mechanism by which evolution unfolds. The environment can influence which traits are advantageous, but the variation itself and the inheritance of traits are biological.