Woman: Don't forget to drop me a line when you settle down.Man: I won't. I'll keep you pos

Woman: Don't forget to drop me a line when you settle down.

Man: I won't. I'll keep you posted.

Question: What does the man mean？

A．He'll write to the woman.

B．He'll tell the woman his new address.

C．He'll visit the woman once in a while.

D．He'll chat with the woman on the phone.