"Best Part of the Body" joke

Mark rents an apartment in New York, and goes to the lobby to put his
name on the group mailbox. While there, an attractive young lady
comes out of the apartment next to the mailboxes wearing a robe.
Mark smiles at the young girl and she strikes up a conversation
with him. As they talk, her robe slips open and it is quite obvious
that she has nothing on under the robe. Poor Mark breaks out into a
sweat trying to maintain eye contact. After a few minutes, she places
her hand on his arm and says, "Let's go in my apartment, I hear someone
coming. . . "
He proceeds with her into the apartment and after she closes the door,
she leans against it allowing her robe to fall completely open. She
purrs at him, "What would you say is my best feature?"
The flustered, embarrassed Mark stammers, clears his throat several
times and finally squeaks out, "Oh, it's got to be your ears!"
She's astounded! "Why my ears? Look at these boobs! They are full,
don't sag and they're all mine! My butt - it's firm, doesn't sag
and has no cellulite! Look at this skin, no blemishes or scars! Why in
heaven's name would you say my ears are the best part of my body?!"
Clearing his throat once again, Mark stammers, "Outside, when you
said you heard someone coming, that was me."