For this item, the most probable answer is letter A. One of the most important reason why Earth is a livable place is its proper distance from the Sun which gives adequate temperature and amount of radiation. Other factors are the gravity, atmosphere, and water.
Uniformitarianism
fossils
radioactive decay
48 million
after
The youngest age of the shale is 910 ka. According to the principle of inclusions, the shale formed before the tephra, so the tephra must be younger than 910 ka.
The planet that takes the least time to revolve the sun is the closest planet so that would be Mercury.
How old the rock is
thats my answer
