Free Main Idea & Detail Recall Practice Questions

1. Passage: Honeybees communicate the location of food sources through a series of movements called the waggle dance. A foraging bee returns to the hive and performs a figure-eight pattern on the comb. The angle of the dance relative to the vertical indicates the direction of the food source relative to the sun, while the duration of the waggle portion signals the distance. Question: What is the main idea of this passage?

• Honeybees use a specific dance to communicate the direction and distance of food sources to other bees
• Honeybees always fly in figure-eight patterns when searching for food
• The sun is the most important factor in a honeybee's ability to find food
• Foraging bees work alone and do not share information with the hive

2. Passage: Coral reefs support 25% of marine species despite covering less than 1% of the ocean floor, providing food, income, and coastal protection. Rising temperatures cause coral bleaching — corals expel symbiotic algae that supply color and nutrients. Scientists estimate 90% of reefs could be severely degraded by 2050. What is the main idea of this passage?

• Coral reefs are ecologically and economically vital but face severe threats from rising ocean temperatures
• Coral bleaching is a natural process that reefs recover from quickly
• Marine species do not depend on coral reefs for survival
• Ocean temperatures have remained stable over the past century

3. Passage: During the Industrial Revolution, factories relied on water wheels and steam engines. AC motors in the late 1800s allowed factories to be built away from rivers and coal supplies, enabling urban mass production and rapid city growth. The steam-to-electric transition is considered one of the most significant technological changes in modern history. Which detail is directly stated in the passage?

• Alternating-current motors allowed factories to be located away from rivers and coal supplies
• Thomas Edison invented the alternating-current motor
• Steam engines were more efficient than electric motors
• The Industrial Revolution began in the United States

4. Passage: Soil erosion becomes problematic when human activities — deforestation, overgrazing, improper farming — strip vegetation that holds soil in place. Lost topsoil reduces agricultural productivity and pollutes waterways. Terracing, cover cropping, and no-till farming can significantly reduce erosion. What is the main idea of this passage?

• Human activities accelerate soil erosion, harming agriculture and waterways, but conservation practices can help
• Soil erosion is entirely caused by human activity and did not exist before agriculture
• No-till farming is the only effective method for preventing soil erosion
• Waterway pollution is unrelated to farming practices

5. Passage: The precautionary principle holds that protective measures should be taken even when cause-and-effect is not fully established. Critics say it stifles innovation; proponents argue inaction costs far more when threats materialize. The debate centers on technologies like genetic engineering and nanotechnology. What is the main idea of this passage?

• The precautionary principle advocates early protective action against uncertain threats, but its application is debated
• Genetic engineering and nanotechnology have been proven dangerous and should be banned
• Critics of the precautionary principle want to eliminate all environmental regulations
• Scientific proof is always available before a technology causes harm