The IUPAC name of formyl chloride is:

Explanation

The correct IUPAC name for formyl chloride is Methanoyl chloride. This name indicates that the compound is derived from methane (the simplest alkane with one carbon) with a carbonyl group (C=O) and a chlorine atom attached. The prefix 'formyl' corresponds to the presence of the aldehyde functional group, which is equivalent to the methanoyl structure. The other options are incorrect for the following reasons: - Chloro methanoic acid implies the presence of a carboxylic acid group, which is not present in formyl chloride. - Chloro methane suggests a chlorinated methane without considering the carbonyl group, leading to an insufficient description of the compound. - Chloro methanoate implies an ester structure, which is also incorrect as there is no alcohol component in formyl chloride.