D

Step 1: Understand the term 'elastic after effect'. This refers to the tendency of a material to continue deforming even after the applied stress is removed, related to time dependence.
Step 2: Consider each option:
- Copper: Displays both elastic and plastic deformation and does exhibit some elastic after effect.
- Rubber: Known for showing significant elastic and viscous behavior, including elastic after effects.
- Steel: Typically exhibits a clear elastic response, but may have minor elastic after effects depending on its treatment.
- Quartz: A brittle material that behaves elastically up to its limit and does not exhibit significant elastic after effects post-stress removal.
Conclusion: The material that practically does not show any elastic after effect is Quartz.
Therefore, the correct answer is D.