Which of the following statement is incorrect?

• Gateways are assumed to know correct routes; hosts begin with minimal routing information and learn new routes from gateways.
• Layered protocols are designed so that layer n at the destination receives exactly the same object sent by layer n at the source.
• Application programs as well as all protocol software from the Internet layer upward use only IP addresses; the network interface layer handles physical addresses.
• All of the above
• None of the above