What was the smartest species of dinosaur?

Palaeontologists believe that the troodonatinae family- bird -like theropod dinosaurs- was one of the most intelligent. This is based on finds from the trodden genus, which have revealed that the species had an incredibly large brain-to-mass differential, with the dinosaur’s cerebrum-to-brain-volume ratio sitting at 31.5 per cent to 63 per cent on the non-avian side. This, along with the dinosaur’s relatively small size (2.4m long) and broad fossil distribution suggest that for its size it had a very large brain and adapted to conditions with ease.

Yes it looks more ‘Chickenosarous’ than Tyrannosaurus’ but this is the most intelligent dino of them all