A、Under a stone. B、Under the window. C、In the kitchen. D、Near the living room. AWhere did the speaker put his key?

An old friend from abroad, whom I was expecting to stay with, telephoned from the airport to tell me that he had arrived. I was still at the office at the time, but I had made arrangements for his arrival. After explaining where my new flat was, I told him that I had left the key under a stone near the door.As I was likely to be at home rather later, I advised him to go into the kitchen and help himself to food and drink.
    Two hours later, my friend telephoned me from the flat. At the moment, he said, he was listening to some of my re- cords after having just had a truly wonderful meal. He had found a pan on the gas stove and fried two eggs and had helped himself to some cold chicken from the refrigerator. Now he said, he was drinking a glass of orange juice and he hoped I would join him. I asked him if he had reached the flat without difficulty, he answered that he had not been able to find the key under the stone, but fortunately the living-room window just by the apple tree had been open and he had climbed in. I listened to all this in astonishment. There is no apple tree in front of my living room, but there is one in front of my neighbor’s.