Answer: The correct answer is option A.
Step-by-step explanation:
Alloy: An alloy is defined as homogeneous substance composed of two different or more than two different metals. Brass is one alloys made from zinc and copper metal.
Where as compound is a substance made up two or more different elements.
Element is the purest substance which contains atoms of only one kind.
Molecule is the group of atoms of same kind or different kind.
Hence, the correct answer is option A.