Describe three pieces of evidence that support the Big Bang theory

One - people like to bang so the universe probably likes to bang too. (and since the universe is big, it's called the 'big bang')

Two - there's a theory of inflation where when the universe begins, it expands and inflates until it's a big crunch (folds over itself) or becomes another big bang.

Three - We humans feel the need to understand everything - how things were created, how things occur, etc ... & the big bang theory seems legit enough to most people, although there is minimal evidence as we can't exactly see how it happens. (ask an astronomer, most of them try to look for evidence about the big bag theory)