Maxperson
Morkus from Orkus
What are the polymorph rules?
In AD&D the answer is no - Polymorph Other gives the target the intelligence and competence of a frog. (If the change is via Polymorph Self then it's a different situation - the character's mental abilities are unchanged, though s/he may have trouble writing down answers.)
In 5e the answer is less clear, but is probably yes - Polymorph says that "[t]he target’s game statistics, including mental ability scores, are replaced by the statistics of the chosen beast. It retains its alignment and personality." The second sentence implies a general continuity of mental capability (a frog can't be aligned, for instance). So a PC polymorphed into a frog becomes more dim-witted (due to the penalty to INT) but still retains his or her essentially human personality, including alignment and, I would say, IQ-test-taking-ability.
It doesn't imply that at all. Personality is basic. An ornery barbarian polymorphed into a dog will be an ornery dog. A pacifist cleric will be a sedate dog. If it wanted the PC to have continuity of mental capability, it would have said so and not limited it to personality and alignment which are basic attitudes and which do not require continued mental capability.