Passage 1

Every autumn, thousands of monarch butterflies migrate from the northern United States and Canada to central Mexico. The journey can cover up to 3,000 miles. Scientists are still unsure how the butterflies find their way, but many believe they use the sun and Earth’s magnetic field as guides. Despite their fragile wings, monarchs complete the trip in about two months.

Questions

1. What is the main idea of the passage?
   A) Monarch butterflies are fragile creatures.
   B) Monarch butterflies migrate thousands of miles each year.
   C) Scientists know exactly how monarchs migrate.
   D) Monarch butterflies stay in Canada during the winter.\

• The main idea is:

1. ✅ B) Monarch butterflies migrate thousands of miles each year.

• (A) is a detail (fragile creatures).

• (C) is incorrect because scientists do not know exactly.

• (D) is false (they don’t stay in Canada in winter).

2. Which detail supports the main idea?
   A) The journey can cover up to 3,000 miles.
   B) Scientists are still unsure how they find their way.
   C) The butterflies use the Earth’s magnetic field.
   D) They complete the trip in about two months. Passage 

   2. Supporting detail:
      ✅ A) The journey can cover up to 3,000 miles.

   • (B) and (C) explain how they might migrate, not the main idea.

   • (D) is also a detail, but distance (3,000 miles) directly supports the main idea of migration.