A serious answer would be: it depends on the kind of emergency.

But he couldn't bring himself to give it a serious answer.

In fact she stopped to give a serious, thoughtful answer.

I had expected her to smile, not make me a serious answer.

Then he went on to present a serious answer.

He meant this as a joke but it was thought to be a serious answer.

Not perhaps the serious answer you were looking for, but there we are.

I think we have to give very serious answers to a few questions here.

Let us use this opportunity to get serious answers to several questions.

This is a real question and deserves a serious answer.