Task: Instance Description Understanding (ontology: Sciences/Computer_Science)

Which of the following definitions best describes the instance 'picogram'?

A. A mass unit which is equal to one thousandth of one millionth of a gram or 10^[-9] g.
B. A mass unit which is equal to the mass of the International Prototype the instance kept by the BIPM at Svres, France.
C. A mass unit which is equal to one thousandth of a gram or 10^[-3] g.
D. A mass unit which is equal to 10^[-12] g.

Answer: A mass unit which is equal to 10^[-12] g.