Task: Class Definition Understanding (ontology: Sciences/Biology)

Which of the following definitions best describes 'acetyl fluoride'?

A. An organochlorine compound derived from methane, ethane or propane that contains atoms of hydrogen, chlorine, fluorine, and carbon only.
B. A nucleobase analogue that is uracil in which the hydrogen at position 5 is replaced by fluorine. It is an antineoplastic agent which acts as an antimetabolite - following conversion to the active deoxynucleotide, it inhibits DNA synthesis (by blocking the conversion of deoxyuridylic acid to thymidylic acid by the cellular enzyme thymidylate synthetase) and so slows tumour growth.
C. An ether compound having fluoromethyl and 1,1,1,3,3,3-hexafluoroisopropyl as the two alkyl groups.
D. An acyl fluoride that is fluoroethane carrying an oxo group at position 1.

Answer: An acyl fluoride that is fluoroethane carrying an oxo group at position 1.