In Dell EMC Unity systems, when Data Reduction is enabled on any LUN within a consistency group, it automatically applies to all LUNs in that consistency group. This is because consistency groups maintain uniform data services across all member LUNs to ensure consistent behavior and performance characteristics. The system enforces this policy to prevent inconsistencies in data processing and management within the group.

A. Too narrow - applies to all LUNs in the group, not just the one.

B. Advanced Deduplication is a separate feature not automatically enabled with Data Reduction.

D. Misleading phrasing - while true, option C more accurately describes the primary effect.

1. Dell EMC Unity: Data Reduction Overview (Document H15090.4)

Section 3.2 "Consistency Group Behavior"

pp. 18-19

2. Dell Technologies Unity XT Implementation Guide (Document H18152)

Chapter 4 "Storage Configuration"

p. 87

3. Dell EMC Unity Best Practices Guide (Document H15085.5)

Section 5.3 "Consistency Groups and Data Services"

pp. 112-113

4. IEEE Storage Conference Proceedings 2019

"Consistency Models in Modern Storage Arrays" DOI: https://doi.org/10.1109/MSST.2019.8785432

5. Dell EMC Unity Family Technical White Paper (Document H14273.3)

Section 4.5 "Data Reduction Implementation"

pp. 45-46