What property of ARP causes the request to be flooded out all ports of a switch except for the port receiving the ARP request?

Question:
What property of ARP causes the request to be flooded out all ports of a switch except for the port receiving the ARP request?

• The destination MAC address FF-FF-FF-FF-FF-FF appears in the header of the Ethernet frame.
• The type field 0x806 appears in the header of the Ethernet frame.
• Entries in an ARP table are time-stamped and are purged after the timeout expires.
• ARP replies are broadcast on the network when a host receives an ARP request.

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