Mrs. Black lives on Second Avenue. New Year is coming. She wants to send   a card to her friend in Toronto, but she doesn't know where the post office is. She asks her neighbor   Mary, " Is there a post office near here? I want to send a card." "The post office is not near from here," answers Mary, "but you don't need to go to the post office to post the card. There is a _ in front of the supermarket. You can put your card into the mailbox" The post office is   _  .
next to Mary's house not near Mrs. Black's house across from the supermarket in front of Mary's house.