According to Darwin's theory, what leads traits to become common in a population?

• A. It increases survival and reproduction and is passed to offspring
• B. It is acquired by everyone through learning
• C. It is always genetically predetermined in all individuals
• D. It never changes over time

Answer: (A)

Natural selection works through heritable variation. When a trait helps an organism survive or reproduce, that individual leaves more offspring, and because the trait is passed on, it becomes more common in the population over generations. So the reason this trait spreads is not because it’s learned or guaranteed in every individual, but because it enhances reproductive success and is inherited genetically. Traits acquired by learning aren’t generally passed to offspring, and saying traits never change or are fixed in all individuals ignores how variation and inheritance drive evolution.