Please refer to the following short case as you respond to the next question: A painter accepts orders for original works from customers in person or via the Internet. Based on the order, the painter creates an initial sketch, which must be approved by the customer; the customer may make changes to the initial sketch. After customer approval, the painter selects appropriate materials and gives the customer a price quote. If the customer accepts the price quote, the painter creates the original work; if not, the project is abandoned. The painter stores data about customers, previous orders and previously completed works in an electronic database. Data flow diagrams incorporate four symbols. Which of the following pairs of items would be represented with the same symbol in a DFD of the case?

a. Painter, customer

b. Initial sketch, price quote

c. Customer, initial sketch

d. Painter, price quote