Answer : The correct option is, It has three OH groups.
Explanation :
The chemical formula of aluminium hydroxide is, [tex]Al(OH)_3[/tex]
From the chemical formula of aluminum hydroxide, we conclude that there are one number of aluminium atom, three number of oxygen atoms and three number of hydrogen atoms.
Or we can say that there are three OH groups present in aluminium hydroxide compound.
Or we can say that [tex]Al(OH)_3[/tex] this compound represent that there is a one molecule of aluminum hydroxide.
Hence, the correct option is, It has three OH groups.