You are sizing an HPE Alletra 5030.

Detailed Explanation:

Rationale for Correct Answer:

In Alletra 5000/6000 sizing, the Failure Domain Reserve (FDR) is used to account for rebuild overhead in case of drive failure. HPE best practices define that, unless otherwise directed by the sizing tool or customer requirements, the minimum FDR value should be set to 23% of the largest drive size. This ensures enough reserve capacity for fault tolerance and sustained performance during rebuilds.

Distractors:

B/C: Low-read latency is influenced by cache and workload profile, not by arbitrary FDR percentages.

D: Using the smallest drive is incorrect — rebuild impact must be sized against the largest drive.

Key Concept: FDR sizing based on 23% of largest drive = HPE best practice.