Which of the following SCSI interfaces can support the most devices? (Choose all that apply)

A.
Wide SCSI.

B.
Fast SCSI.

C.
Ultra Wide SCSI.

D.
Ultra2 SCSI.

Explanation:
Wide SCSI , Wide Fast SCSI, Ultra Wide SCSI, Wide Ultra2 SCSI, Ultra160 SCSI, Ultra320 SCSI and Ultra640 SCSI all have a data bus width of 16 bits (2 bytes) and can support up to 16 devices, including the host adapter.

Incorrect Answers:
B, D: SCSI-1, Fast SCSI, Ultra SCSI, and Ultra2 SCSI all have a data bus width of 8 bits (1 byte) and can support up to 8 devices, including the host adapter.
References:
Charles J. Brooks, Server+ Certification Exam Cram 2 (Exam SK0-002), QUE Publishing, Indianapolis, 2006, pp. 143-147.