Christianity then, and no I have to specify why it's a better answer than that put forward by any other religion, I'm just using my religion.
So
how did the Universe happen, then, according to Christianity?
Let's be clear on this. Science doesn't care
who. It doesn't care if the Universe was created as an illegitimate lovechild of copulating multiverses. It doesn't care if the first quantum function was defined by Allah. It doesn't care if we are all figments of the Flying Spaghetti Monster's imagination.
It only cares
how the Universe came to be.
So
how does Christianity say the Universe came to be?
In the beginning, there was void and the darkness.
Then God said: let there be light.
Where did the void come from? Where did the darkness come from? Who is God and where did
he come from?
How did he create the light? Did he shoot photons from his fingertips? Did he touch off the singularity that caused the Big Bang? Did he set off a quantum bomb?
These are questions that Chirstianity
refuses to answer. Like the question of the "Holy Trinity"... you've just got to take it on faith. Now sit down and shut up and say ten Hail Marys.
Christianity doesn't delve into the mechanics of building a Universe. It simply says that one day, it was there.
It
can't answer the question at all. Not a hundred years or a thousand years worth of theological texts satisfactorily explain where God came from. They just define it as something they can't know and leave it at that.
Edit:
In the end, Science merely describes the mechanistic aspect of the Universe. All it cares is that a bowling ball falls down. It doesn't care whether the bowling ball fell off a ledge due to the wind, was pushed off by someone or dropped by a passing bird. It merely describes how the bowling ball falls and attempts to define the mechanism by which the falling occurs. Religion, on the other hand, asserts that the ball was dropped by the hand of God. As God apparently has no fingerprints nor material representation, Science can neither prove nor disprove this.
Some religious fundamentalists even go so far as to say that the bowling ball buried in that crater in the pavement is there because it was always there... (this is your so-called "Intelligent Design") and that's not an answer that's satisfactory to anyone but the uncurious.