You have a file server named Server1 that runs Windows Server 2003 Service Pack (SP2). Server1 has a 10-gigabit network adapter and is connected to a 100-Mb switch. You replace the 100-Mb switch by using a 1-GB switch. You discover that copying files to Server1 over the network is slow. You need to reduce the amount of time it takes to copy files to Server1 over the network. Which connection type should you specify for the network adapter? （）

A. 1-gigabit half-duplex
B. 1-gigabit full-duplex
C. 10-gigabit half-duplex
D. 10-gigabit full-duplex