Which best supports the evidence that an asteroid collision may have caused the extinction of dinosaurs?

Question

Many dinosaur skeletons are found in one particular rock layer.
Many dinosaur skeletons are found in one particular rock layer.

Rare metal on Earth called Iridium is found in layers where dinosaurs disappeared.
Rare metal on Earth called Iridium is found in layers where dinosaurs disappeared.

Dinosaur fossil remains are found at the bottom of a body of water.
Dinosaur fossil remains are found at the bottom of a body of water.

Bodies of dinosaurs are only found in craters where asteroid collided.
Bodies of dinosaurs are only found in craters where asteroid collided.

Answer 1

The statement that best supports the evidence that an asteroid collision may have caused the extinction of dinosaurs is:

"Rare metal on Earth called Iridium is found in layers where dinosaurs disappeared."

This is significant because iridium is more commonly found in asteroids than on Earth, and the presence of an iridium layer in the geological record corresponds with the time of the dinosaurs' extinction (about 66 million years ago). This provides strong evidence for the hypothesis that an asteroid impact contributed to the mass extinction event.