A user is reporting that a large file upload is slower to one particular server compared to other servers on the same network. Which of the following might account for the difference in upload speed?

An incorrect subnet mask would cause routing failures or inability to communicate with hosts on certain subnets, not a selective slowdown in upload speed to a reachable server.

Whether an IP address is assigned via DHCP or configured statically has no effect on the throughput or speed of data transfers once the connection is established.

Full-duplex allows simultaneous transmission and reception on a network interface, effectively doubling the available bandwidth for a given link speed. When the duplex is set to half, the interface can only send or receive at any given moment, and collisions occur when both sides attempt to transmit simultaneously, triggering retransmissions that further degrade throughput. This would explain why uploads to this specific server are slower while other servers on the same network with correct duplex settings perform normally.

Using private addressing on a LAN server does not affect transfer speed because internal traffic never requires public address routing.

An incorrect default gateway would prevent the server from communicating with hosts on other networks, but would not cause degraded upload speeds for traffic that has already reached the server.