Which of the following hard drives has the largest capacity?

This question assesses the understanding of data storage capacity units. The units must be compared on a common basis. The hierarchy of standard decimal units is: Kilobyte (KB), Megabyte (MB), Gigabyte (GB), and Terabyte (TB). Each unit is approximately 1,000 times larger than the previous one. 2 Terabytes (TB) = 2,000 Gigabytes (GB) = 2,000,000 Megabytes (MB). 4,000 Megabytes (MB) = 4 Gigabytes (GB). 100 Gigabytes (GB) is simply 100 GB. 50 Kilobytes (KB) is approximately 0.05 MB. By converting all options to a common unit like Gigabytes (2,000 GB, 0.00005 GB, 100 GB, and 4 GB), it is clear that 2TB is the largest capacity.

B. 50KB: A Kilobyte (KB) is a very small unit of measurement, thousands of times smaller than a Megabyte and millions of times smaller than a Gigabyte.
C. 100GB: A Gigabyte (GB) is a smaller unit than a Terabyte (TB). One Terabyte is equivalent to 1,000 Gigabytes, making 100GB significantly smaller than 2TB.
D. 4,000MB: While 4,000 is a large number, the unit Megabyte (MB) is smaller than a Gigabyte. 4,000MB is equivalent to only 4GB, which is far less than 2TB (2,000GB).

1. Brookshear, J. G., & Brylow, D. (2019). Computer Science: An Overview (13th ed.). Pearson. In Chapter 1, Section 1.4, "Representing Information as Bit Patterns," the text defines the hierarchy of byte multiples, stating that "kilo" implies a thousand, "mega" a million, "giga" a billion, and "tera" a trillion, establishing the relative sizes.

2. Stanford University. (n.d.). CS101, Lecture 02: The Guts of a Computer. Stanford Engineering Everywhere. In the section "Bits and Bytes," the course material explains the prefixes for data storage: "A kilobyte (KB) is 1000 bytes... A megabyte (MB) is 1 million bytes... A gigabyte (GB) is 1 billion bytes... A terabyte (TB) is 1 trillion bytes." This confirms that TB is the largest unit listed.

3. National Institute of Standards and Technology (NIST). (2008). The International System of Units (SI). (NIST Special Publication 330). p. 31, Table 5. This official publication defines the SI prefixes, where tera- (T) represents a factor of 10¹², giga- (G) is 10⁹, mega- (M) is 10⁶, and kilo- (k) is 10³. This standard confirms the multiplicative factors and relative order of the units.