Answer : There are three different types of atoms present in one molecule of aluminium hydroxide,

Explanation :
The given molecules is aluminium hydroxide,

In aluminium hydroxide
molecule, there are three different types of atoms present. The three different atoms are, aluminium, hydrogen and oxygen.
In aluminium hydroxide
molecule, there are one atom of aluminium, three atoms of hydrogen and three atoms of oxygen.
Hence, there are three different types of atoms present in one molecule of aluminium hydroxide,
