The polymer containing strong intermolecular forces e.g. hydrogen bonding, is

Hydrogen bonding arises when a hydrogen atom is covalently attached to a highly electronegative atom such as $$N$$, $$O$$ or $$F$$ and comes sufficiently close to another electronegative atom possessing a lone-pair of electrons.

Therefore, polymers that contain functional groups like $$-CONH-$$ (amide), $$-OH$$ (hydroxyl) or $$-NH_2$$ (amine) can form strong intermolecular $$\text{H}$$-bonds with neighboring chains, leading to high tensile strength and high melting/softening points.

Examine each option:

Option A (Teflon, $$CF_2-CF_2-$$)
Its backbone and side groups are only $$C-C$$ and $$C-F$$ bonds. Although the $$C-F$$ bond is polar, there is no hydrogen directly bonded to $$N$$, $$O$$ or $$F$$; thus hydrogen bonding is absent. Interchain forces are only weak van der Waals interactions.

Option B (Nylon 6,6, $$[-NH-(CH_2)_6-NH-CO-(CH_2)_4-CO-]_n$$)
Each repeating unit contains two amide $$-CONH-$$ linkages. The $$N-H$$ hydrogens can hydrogen-bond with the carbonyl oxygens of neighboring chains. Hence nylon 6,6 possesses extensive intermolecular $$\text{H}$$-bonding, giving it great strength and rigidity.

Option C (Polystyrene, $$[-CH_2-CH(Ph)-]_n$$)
Its chain contains only $$C-C$$ bonds with pendant phenyl rings. No $$N-H$$ or $$O-H$$ groups are present, so hydrogen bonding is not possible; interactions are mainly weak dispersion forces.

Option D (Natural rubber, cis-polyisoprene, $$[-CH_2-C(CH_3)=CH-CH_2-]_n$$)
Again, only $$C-C$$ and $$C=C$$ bonds exist. Absence of $$N-H$$ or $$O-H$$ groups means no hydrogen bonding; forces are weak van der Waals.

Thus, the only polymer among the given choices that contains groups capable of forming strong intermolecular hydrogen bonds is nylon 6,6.

Final answer: Option B which is: nylon 6,6