$7.$ Sydney Airport Limited owns Sydney Airport. The company offers international and

domestic passenger services. It is also involved in leasing, marketing, brand space,

and advertising for retail, food, and dining portfolio; property and car rental, and

hotel business; and landside operations and transport business inside the Sydney

Airport. Buyers of the service of Sydney Airport Limited in the Porter$$s five forces

framework refer to

a$.$ International and domestic passengers

b$.$ International and domestic airlines

c$.$ Retail stores

d$.$ All of the above