Text 1: Astronomer Park argues that comets brought significant amounts of water and organic compounds to the early Earth. Studies of comet composition have revealed water with isotope ratios similar to Earth's oceans and amino acids that are building blocks of life.
Text 2: Astronomer Singh accepts that comets contain water and organics but disputes how much they contributed to early Earth. Newer measurements show that the isotope ratios in many comets do not match Earth's oceans as well as initial studies suggested; asteroids, she argues, were probably the primary water source.
Both authors would most likely agree that
- A
comets are made of metallic iron.
- B
all of Earth's water came from comets.
- Ccheck_circle
comets contain water and organic compounds.
- D
Earth's oceans are unrelated to space objects.
Explanation
Both accept that comets contain water and organics; they differ on how much they contributed. A is shared. B, C, and D contradict at least one author.