Terrell and Monique Anderson run an antique store in their h…

Terrell and Monique Anderson run an antique store in their hometown of Dayton, Ohio. To find items to sell in their shop, they travel around the United States and Europe buying unique artifacts. Within an hour of making a purchase, they use their smartphone to take a picture of the item and post a short tweet about the item on Twitter. Then, they ship the item back to Dayton for sale in their shop. Which symbol should be used to represent Twitter in a context diagram of this process?