Union Soup Kitchen is a non-profit organization that collects, stores,
prepares and provides food to the homeless in Erie, Pennsylvania. Donations
of food are recorded in a database and a receipt is provided to the donor.
When food is used, the database is updated so that it always reflects the
amounts and types of food that are available. In a data flow diagram, which
type of symbol would be used to represent the flow of data from the donor
into the system?