The following table gives the damping ratio and output characteristic

Row No.	Damping ratio	Response
1	δ = 0	Critically damped
2	0 < δ < 1	Under damped
3	δ = 1	Over damped
4	δ > 1	Un damped

Correct relation is

Concept:

The damping ratio (ζ = c/cc) is a system parameter, that can vary from un-damped (ζ = 0), under-damped (ζ < 1) through critically damped (ζ = 1) to over-damped (ζ > 1)

Overdamped System: ζ > 1

This is the equation of aperiodic motion i.e. the system cannot vibrate due to over-damping. The magnitude of the resultant displacement approaches zero with time.

Underdamped: ζ < 1

This resultant motion is oscillatory with decreasing amplitudes having a frequency of ωd. Ultimately, the motion dies down with time.

Critical Damping: ζ = 1

The displacement will be approaching zero in the shortest possible time.