

I'm gonna have to go with the T-Rex's.
Godzilla... Truly a God incarnate.

T-rex...I could hide from it...Megas...I'm a good swimmer, but they're Sharks, so I have a slim chance surviving the T-rex scenario, and zero vs Megas.
IN SPACE THERE IS NO WARNING

GODZILLA: KING OF THE MONSTERS - Oh, this is a very dreadful choice! Hmm. After careful consideration, I believe I will go with the T-Rex pack. I am a fair-decent swimmer. However, I do not believe that would avail me against the 19 meter sharks! :)

GODZILLA: KING OF THE MONSTERS - Oh, and I would also begin weeping. Quite alot! :)

I choose T.rex, because I would feel honoured to be killed by the greatest dinosaur of all time
"Part of the journey is the end..."

It's always been a deep illogical fear whenever I've swam in a lake or ocean to look down underwater and see something coming up for me.
So T- rex for me though death through being eaten would probably be one of the worst ways to go.

GODZILLA: KING OF THE MONSTERS - yes, there's that. Furthermore, if I have to be eaten alive by something... well, let it be the Tyrant King!

Ermahgerd, the only choice would have to be T-Rex. I mean T-Rex is just one fear in general, but Megalodon... That's deep ocean water (a classic fear of mine) AND a shark... a leviathan shark at that.
Given that I feel like I would die of sheer fear at the sight of both, I would at least have a slim shot at getting away from the T-Rexs.

I myself am good at swimming, but there is no way I can outspeed a pack of hungry Megalodon. And I can't outrun a pack of T.rex either. However, I chose T.rex since I would feel honoured to be eaten by my favourite dinosaur
"Part of the journey is the end..."

I'm a pretty good swimmer, but I think it's easier to get tired swimming than running. Also I don't believe T. rex was as fast as it was in Jurassic Park, and you could possibly outrun them/find somewhere to hide easier.
“Banana oil.”- George Takei, Gigantis: The Fire Monster