💾 Data Sizes & Units

Option C is the most professional because it converts to the most natural unit for this size (gigabytes), shows the intermediate step in megabytes for clarity, and uses an exact conversion rather than rounding too aggressively. 1,572,864 KB ÷ 1,024 = 1,536 MB. 1,536 MB ÷ 1,024 = 1.5 GB exactly. Option B is acceptable in casual conversation but skips the intermediate unit. Option A leaves a technical client doing the mental conversion — unhelpful. Option D uses "approximately 1,500,000" when we can give the exact figure. General rule: always convert data sizes to the most human-readable unit. For storage discussions, use GB or TB. For memory, MB or GB. For file sizes, KB, MB, or GB depending on magnitude.

Option C is technically correct and the only answer that makes the distinction precise. MB (SI prefix, base-10) = 1,000,000 bytes. MiB (IEC prefix, base-2) = 1,048,576 bytes. The difference at scale: 10 MB = 10,000,000 bytes; 10 MiB = 10,485,760 bytes — a difference of 485,760 bytes (~474 KB). This matters for: API payload limits, disk partitioning, memory allocation specs, and network capacity planning. Options A and D are technically incorrect and would cause bugs in edge-case payload handling. Option B downplays the difference. In professional technical writing, always use the correct unit. RAM manufacturers use GiB; hard drive manufacturers use GB (which is why a "1 TB" drive shows 931 GiB in your OS).