Q: Among solids, the highest melting point is exhibited by 

Explanation:
Covalent solids exhibit the highest melting points among all types of solids. This is because covalent solids consist of a vast network of atoms bonded together by strong covalent bonds. These bonds are continuous throughout the entire structure, creating a rigid and stable lattice that requires a large amount of energy to break.

In comparison, ionic solids, while also having strong bonds due to the electrostatic attraction between ions, generally have lower melting points than covalent network solids. This is because the bonds in ionic solids can be overcome more easily under heat.

Molecular solids are held together by weaker intermolecular forces such as van der Waals forces or hydrogen bonds. These forces are much easier to break, resulting in significantly lower melting points.

The term “pseudo solids” is not a standard classification in chemistry and does not represent a category with high melting points.

Therefore, among the options provided, covalent solids have the highest melting points due to their strong and extensive covalent bonding throughout the entire structure.