Which of the following SCSI signaling systems supports a ribbon cable with an IDC 50 connector?

A.
High-Voltage Differential (HVD)

B.
Low-Voltage Differential (LVD)

C.
Differential (DIFF)

D.
Single-Ended (SE)

Explanation:
Wide Ultra2 SCSI, Ultra2 SCSI, Ultra160 SCSI, Ultra320 SCSI and Ultra640 SCSI use Low-Voltage Differential (LVD) signaling and supports a bus length of 12 meters.
Incorrect
Answers:
A, C: High-Voltage Differential (HVD) signaling, which is also called Differential (DIFF) signaling, provides reliable signals in a high-noise environment over cable lengths of up to 25 meters.
D: Single-Ended (SE) signaling is uses on internal ribbon cable with an IDC 50 connector and a maximum cable length of 1.5 meters.
References:
Charles J. Brooks, Server+ Certification Exam Cram 2 (Exam SK0-002), QUE Publishing, Indianapolis, 2006, pp. 143-147.
Brad Hryhoruk, Diana Bartley, and Quentin Docter, Server+ Study Guide (2nd Edition), Sybex, Alameda, CA, 2002, pp. 119-120.