What mechanism did Darwin propose to explain evolutionary change?

• A. Inheritance of acquired characteristics
• B. Catastrophism
• C. Natural selection
• D. Use and disuse

Answer: (C)

Natural selection is the mechanism Darwin proposed to explain evolutionary change. In any population, individuals vary in traits, and those variants that help individuals survive and reproduce in a given environment become more common over generations. Because these advantageous traits are heritable, they are passed on to offspring, gradually shifting the population’s characteristics. Variation arises through mutation and genetic recombination, and selection acts on this variation without any conscious direction—it's the differential success of individuals with favorable traits that drives adaptation. This idea contrasts with the notion that acquired traits are inherited, that dramatic single events drive all change, or that use and disuse determines inheritance.