SI units — practice question

Which statement that uses prefixes of the base unit metre (m) is incorrect?

• A$1\,\text{pm} = 10^{-12}\,\text{m}$
• B$1\,\text{nm} = 10^{-9}\,\text{m}$
• C$1\,\text{Mm} = 10^{6}\,\text{m}$
• D$1\,\text{Gm} = 10^{12}\,\text{m}$