Answer : 3. "Lead(II) oxide"
Explanation :

Answer: C) Lead(II) oxide Explanation: The systematic name for a chemical is the unique name given to it by the International Union of Pure Applied Chemistry (IUPAC). The IUPAC name can differ from a chemical compound's general name.   PbO is an ionic compound since it consists of a Lead as metal and Oxygen as nonmetal. The systematic name for PbO is Lead (II) oxide. Here we need to put the (II) since lead has more than one combining capacity.