Which is the strongest type of intermolecular force between solute and solvent in br2 (l) in ccl4 (l) ?

Br₂ is a completely non-polar molecule as it has two bromine atoms of equal electronegativities, which results in no dipole moment. CCl₄ is also a completely non-polar molecule. Although, there is a dipole moment for every C-Cl bond in the molecule. But since the structure of CCl₄ is tetrahedral, this results in every dipole cancelling out which provides an overall molecule with no dipole moment.

Since both molecules are non-polar with no net dipole moments, and there are no hydrogens capable of hydrogen-bonding, the only intermolecular forces between the two species are van der waals forces, more specifically London dispersion forces.

The London dispersion forces are instantaneous dipole moments created when the two molecules interact which causes a very weak attraction.