Intermolecular forces are the attractive forces that exist between molecules. In the case of solid hydrogen, the correct answer is option 'B', which refers to van der Waal forces or London dispersion forces.

Van der Waal forces or London dispersion forces are weak intermolecular forces that exist between all molecules, whether they are polar or nonpolar. These forces arise from temporary fluctuations in electron distribution, resulting in the formation of temporary dipoles. These temporary dipoles induce dipoles in neighboring molecules, leading to an attractive force between them.

Below is a detailed explanation of why van der Waal forces are the predominant intermolecular forces in solid hydrogen:

1. Covalent Forces: Covalent forces are strong intramolecular forces that hold atoms together within a molecule. However, they are not relevant to intermolecular forces in solid hydrogen as they involve the sharing of electrons within a molecule, not between molecules.

2. Hydrogen Bonds: Hydrogen bonds are a special type of intermolecular force that occurs when a hydrogen atom is bonded to a highly electronegative atom (such as oxygen, nitrogen, or fluorine) and forms a weak bond with another electronegative atom. Although solid hydrogen molecules contain hydrogen atoms, they do not have the necessary electronegative atoms to form hydrogen bonds.

3. Van der Waal Forces or London Dispersion Forces: Van der Waal forces or London dispersion forces are the intermolecular forces that arise due to temporary fluctuations in electron distribution. In solid hydrogen, the hydrogen molecules are nonpolar, meaning they have an equal distribution of electrons. However, even in nonpolar molecules, there are temporary fluctuations in electron distribution, which result in the formation of temporary dipoles. These temporary dipoles induce dipoles in neighboring molecules, leading to an attractive force between them. In the case of solid hydrogen, these London dispersion forces are the predominant intermolecular forces.

In summary, the correct answer is option 'B' because van der Waal forces or London dispersion forces are the predominant intermolecular forces in solid hydrogen. These forces arise due to temporary fluctuations in electron distribution, leading to the formation of temporary dipoles and attractive forces between molecules.