I. An atom is the smallest unit of an element and a molecule is made up of two or more atoms chemically bonded together. II. An atom is indivisible and a molecule can be broken down into atoms.

III. An atom is the smallest unit bonded together and a molecule is made up of elements.

IV. An element is the smallest unit of an atom and a molecule is made up of two or more metal and non-metal atoms chemically bonded together.
Which conclusion(s) best elaborate on the difference(s) between an atom and a molecule?
A) I & II
B) II & III
C) III & IV
D) IV & I