Exoplanets — planets orbiting stars other than the Sun — were once theoretical. Since the first confirmed detection in 1995, astronomers have catalogued more than 5,000, ranging from gas giants larger than Jupiter to rocky worlds smaller than Earth. The diversity of these systems has overturned the long-held assumption that our solar system was a typical model.
Which choice best states the main idea of the text?
- A
The first exoplanet was discovered in 1995.
- Bcheck_circle
Exoplanet discoveries have revealed a planetary diversity that challenges old assumptions about our solar system.
- C
Most exoplanets are gas giants.
- D
Astronomers should focus on Earth-like exoplanets.
Explanation
The text moves from history to the central insight: diversity has overturned old assumptions — A. B is a date; C is unsupported; D is not argued.