Which best explains how scientists confirmed that the Moon formed around the same time as Earth?

• A. Radiometric dating of rocks from both the Moon and Earth shows similar ages.
• B. The Moon and Earth have identical atmospheric compositions.
• C. The Moon's orbit matches the Earth's rotational period.
• D. The Moon contains large amounts of liquid water, just like Earth.

Answer: (A)

Verified step by step guidance

1. Understand that the question is about how scientists determined the relative ages of the Moon and Earth, focusing on evidence that supports their formation times.
2. Recognize that radiometric dating is a method used to determine the age of rocks by measuring the decay of radioactive isotopes within them.
3. Know that scientists collected rock samples from both the Moon (via lunar missions) and Earth, then performed radiometric dating to find their ages.
4. Compare the radiometric ages of the Moon rocks and Earth rocks; similar ages suggest that the Moon and Earth formed around the same time.
5. Conclude that this evidence is stronger and more direct than other options like atmospheric composition, orbital periods, or presence of water, which do not provide precise formation timing.