Read the following article and select the best answer. Article: As a young child, I was quiet and shy. I was also sick for a long time. My parents worked, and I spent a lot of time at my grandparent's home. While my grandmother cleaned the house and cooked, my grandfather played with me. I was six when my grandfather died. A few months before he died, he gave me a beautiful blue and white blanket . I loved the blanket very much because it made me think of my grandfather. But after a few years, the blanket didn't look very good. It had holes and was dirty. I didn't want to throw the blanket away, so my mother made the blanket into a book bag. I was proud of the book bag, and I used it to carry my books to school every day for a few years. Then the book bag was broken. I begged my mother to make something out of it. She made it into a pencil-box. After a few months, the pencil-box was broken, too. By then I could sew , and I made the pencil-box into a small wallet. I used it for three years, but one day I lost it. I felt sad. My friends and family said, "Forget about it, Paul. You can't make something out of nothing." I thought about it for a while. I decided my friends and family were wrong. There was a way to make something out of nothing. I wrote down the story of my grandfather's blanket. Question: Paul felt sad when he lost _ one day. - the blanket - the book bag - the wallet - the pencil-box
A:
the wallet