Answer:
He informs the listener that the story was not real and provides a moral.
Step-by-step explanation:
Orson Welles presents himself, out of character, to explain that the broadcast was not about a real (even though they did announce it in the beginning). Many people didn't question what was being said on the Radio, which caused a mass hysteria. That consequence seems to be unintended, as Orson explained:
"You will be relieved, I hope, to learn that we didn't mean it, and that both institutions are still open for business. So goodbye, everybody, and remember, please, for the next day or so, the terrible lesson you learned tonight. That grinning, glowing, globular invader of your living room is an inhabitant of the pumpkin patch, and if your doorbell rings and nobody's there, that was no Martian; it's Halloween."