Two ways for that guy to handle it:
1. Politely inform the woman that it’s none of her business. Then shut the door.
2. Tell her a long, rambling story, about nothing really. Maybe how shoe sizes evolved from ancient times. Make things up as you go along. Do not allow her to interrupt. After all, you let her speak first.
If I was in a hurry, I’d go with option 1. Otherwise, I’d go with option 2, just for my own amusement. I’ve done that with scam phone callers.
3rd way to handle it (at least with Jehovah Witnesses).
Had 2 Jehovah witnesses come to my place (4 miles off the paved road) to harangue me about the Lord, had them sit at the table on the front porch, I sat and listened for about five minutes.
Got up and told them I would bring some refreshments (it was a hot day) and brought out a bottle of whiskey and 3 glasses.
They got up and left, I had a good whiskey and a good laugh.