Cambridge Secondary (7-9). Stage 9. Science. Learner's Book - Unit 6: Sound and space

Question 53

Which of these statements could explain why the composition of rocks on the Earth and on the Moon is very similar? Write one letter.

The Moon is mostly formed from Theia’s rocks and the Earth only has a small quantity of Theia’s rocks.
The Earth is mostly formed from Theia’s rocks and the Moon only has a small quantity of Theia’s rocks.
Rocks from Theia and Earth were completely mixed during the collision.