You are trunking Switch A and Switch B together. On Switch A you have the default of switchport mode dynamic auto. On Switch B, which command will you need to configure to allow trunking?

Switch B will need to have its interface set to either switchport mode trunk or switchport mode dynamic desirable for Switch A to turn its interface into a trunk. The commands switchport mode dynamic trunk and switchport mode dynamic auto are incorrect. The command switchport nonegotiate is incorrect as it will never negotiate a trunking protocol.