Option 1: Banking -> This is a service sector activity, classified as an invisible item.
Option 2: Shipping -> This represents freight and transportation services, which are invisible items.
Option 3: Machinery -> This is a physical, tangible good that can be seen and touched, making it a visible item.
Option 4: Tourism -> This involves services like hospitality and travel, classified as invisible items.
Hence, Option 3: Machinery -> Invisible items refer to services and intangible transactions in international trade such as banking, insurance, shipping, and tourism. Machinery is a physical commodity that falls under visible trade (merchandise trade) in the Balance of Payments. Visible items are tangible goods that can be physically seen and measured, while invisible items are intangible services and transfers. -> correct