In this case, the tendency to form hydrogen bonds (bridges) provides a substance more viscous character as long as the intermolecular forces strengthen, in such a way, the substance with the highest tendency to form the aforesaid bonds is the ethylene glycol, , due to its two hydroxiles in its structure.
If ∆H is negative (exothermic reaction), then in order to maintain ∆G<0 which is the condition for spontaneity; T must decrease. This is because, decrease in T will keep the difference of ∆H and T∆S at a negative value in order to satisfy the above stated condition for spontaneity.