Which of the following allowed for the radiation of the dinosaurs?

a- an asteroid impact at the end of the cretaceous period

b- the beginning of the cenozoic era

c-triassic period mass extinction

d- the cambrian explosion

A, it ended all life

Okay, I'm pretty sure it's A. (Even though nobody actually KNOWS what caused the end of the dinosaurs, that is one of the most accepted theories for their extinction.) Also the Cretaceous period was the last Mesozoic period:) (and I think you meant 'eradication' not 'radiation' :P)

Mitosis is one and the other is metoisis