Which specification for connectivity is currently used in data centers for cost and simplicity?

A. 10GBase-T
B. 40GBase-T
C. 10GBase-CX
D. 100GBase-TX

C. 10GBase-CX is commonly used in data centers. It is referred to by its nickname of Twinax. It is a fixed, balanced coaxial pair that can be run up to 25 meters.