Prior to vs. before

Hello teachers,

Please see the sentence bellow:

[color=blue]Dinosaurs became extinct sixty-four million years … first people were ever appeared on earth.

1/ prior to the
2/ before the

Which one is the correct answer? And why?

Thanks in advance


Prior to something: prior to your departure (‘prior to’ cannot be followed by a clause).

Before something or
before + clause: before you leave

Will that help you find the correct answer?

Hi Conchita,

Thanks so much.
It does help.