The observed generational increase in IQ test scores across populations over time likely due to improved education nutrition and environmental factors.

• A. Aptitude Test
• B. Stereotype Threat
• C. Achievement Test
• D. Flynn Effect

Answer: (D)

This question hinges on the Flynn Effect—the observed rise in IQ scores across generations. It’s thought to result from environmental changes such as better education, nutrition, healthcare, and more cognitively demanding environments, which boost test performance even if underlying genetics stay the same. Because of this, population-wide increases over time are best explained by these environmental factors rather than innate changes. The other terms don’t describe a broad, generational upward trend: an aptitude test assesses potential rather than realized performance over time; stereotype threat explains how context can depress performance for some groups in testing; an achievement test measures what someone has already learned.