Which of the following is the correct abbreviation for milliliter?

• A. mmL
• B. ML
• C. ml
• D. mL

Answer: (D)

Verified step by step guidance

1. Understand that the abbreviation for milliliter follows the convention where the prefix symbol is lowercase and the unit symbol is uppercase if it is derived from a proper noun. 'Milli' is a prefix meaning 10^{-3} and is always lowercase 'm'. 'Liter' is abbreviated as 'L', which is uppercase to avoid confusion with the number 1.
2. Review the options given: 'mmL', 'ML', 'ml', and 'mL'.
3. Analyze each option: 'mmL' has two 'm's which is incorrect because only one 'm' is needed for 'milli'; 'ML' uses uppercase 'M' which stands for mega (10^{6}), not milli; 'ml' uses lowercase 'l' which can be confused with the number 1; 'mL' uses lowercase 'm' for milli and uppercase 'L' for liter, which is the correct convention.
4. Recall that the International System of Units (SI) recommends using 'L' for liter to avoid confusion, so the correct abbreviation for milliliter is 'mL'.
5. Conclude that the correct abbreviation for milliliter is 'mL' because it correctly combines the prefix 'm' for milli and the unit 'L' for liter.