Evidence

Evidence is something that is used to support an argument. It gives examples of why something is true.

The Simple English Wiktionary has a definition for: evidence.

For example, if someone come across a cup of spilled milk, that person could look for evidence as to how the milk was spilled. If hairs of a cat and paw prints were found on the ground, they could be evidence that a cat was the cause of the spilled milk. If a witness saw the cat spilling the milk, her testimony would also be evidence.